Phosphodiesterases

ABSTRACT

The invention provides human phosphodiesterases (HPDE) and polynucleotides which identify and encode HPDE. The invention also provides expression vectors, host cells, antibodies, agonists, and antagonists. The invention also provides methods for diagnosing, treating, or preventing disorders associated with aberrant expression of HPDE.

This application is the National Stage of International Application No.PCT/US01/02649, filed on Jan. 26, 2001, which claims the benefit under35 U.S.C. §119(e) of U.S. Provisional Application Ser. No. 60/178,570,filed Jan. 28, 2000, and claims the benefit of U.S. ProvisionalApplication Ser. No. 60/182,042, filed Feb. 11, 2000, and claims thebenefit of U.S. Provisional Application Ser. No. 60/183,178, filed Feb.17, 2000, the contents all of which are hereby incorporated herein byreference.

TECHNICAL FIELD

This invention relates to nucleic acid and amino acid sequences ofphosphodiesterases and to the use of these sequences in the diagnosis,treatment, and prevention of eye, neurological, cardiovascular, cellproliferative, and autoimmune/inflammatory disorders, and in theassessment of the effects of exogenous compounds on the expression ofnucleic acid and amino acid sequences of phosphodiesterases.

BACKGROUND OF THE INVENTION

Phosphodiesterases make up a class of enzymes which catalyze thehydrolysis of one of the two ester bonds in a phosphodiester compound.Phosphodiesterases are therefore crucial to a variety of cellularprocesses. Phosphodiesterases include DNA and RNA endonucleases andexonucleases, which are essential for cell growth and replication, andtopoisomerases, which break and rejoin nucleic acid strands duringtopological rearrangement of DNA. A Tyr-DNA phosphodiesterase functionsin DNA repair by hydrolyzing dead-end covalent intermediates formedbetween topoisomerase I and DNA (Pouliot, J. J. et al. (1999) Science286:552-555; Yang, S.- W. (1996) Proc. Natl. Acad. Sci. USA93:11534-11539).

Acid sphingomyelinase is a phosphodiesterase which hydrolyzes themembrane phospholipid sphingomyelin to produce ceramide andphosphorylcholine. Phosphorylcholine is used in the synthesis ofphosphatidylcholine, which is involved in numerous intracellularsignaling pathways, while ceramide is an essential precursor for thegeneration of gangliosides, membrane lipids found in high concentrationin neural tissue. Defective acid sphingomyelinase leads to a build-up ofsphingomyelin molecules in lysosomes, resulting in Niemann-Pick disease(Schuchman, E. H. and S. R. Miranda (1997) Genet. Test. 1:13-19).

Glycerophosphoryl diester phosphodiesterase (also known asglycerophosphodiester phosphodiesterase) is a phosphodiesterase whichhydrolyzes deacetylated phospholipid glycerophosphodiesters to producesn-glycerol-3-phosphate and an alcohol. Glycerophosphocholine,glycerophosphoethanolamine, glycerophosphoglycerol, andglycerophosphoinositol are examples of substrates for glycerophosphoryldiester phosphodiesterases. A glycerophosphoryl diesterphosphodiesterase from E. coli has broad specificity forglycerophosphodiester substrates (Larson, T. J. et al. (1983) J. Biol.Chem. 248:5428-5432).

Cyclic nucleotide phosphodiesterases (PDEs) are crucial enzymes in theregulation of the cyclic nucleotides cAMP and cGMP. cAMP and cGMPfunction as intracellular second messengers to transduce a variety ofextracellular signals including hormones, light, and neurotransmitters.PDEs degrade cyclic nucleotides to their corresponding monophosphates,thereby regulating the intracellular concentrations of cyclicnucleotides and their effects on signal transduction. Due to their rolesas regulators of signal transduction, PDEs have been extensively studiedas chemotherapeutic targets (Perry, M. J. and G. A. Higgs (1998) Curr.Opin. Chem. Biol. 2:472-481; Torphy, J. T. (1998) Am. J. Resp. Crit.Care Med. 157:351-370).

Cyclic Nucleotide Phosphodiesterase Families

Families of mammalian PDEs have been classified based on their substratespecificity and affinity, sensitivity to cofactors, and sensitivity toinhibitory agents (Beavo, J. A. (1995) Physiol. Rev. 75:725-748; Conti,M. et al. (1995) Endocrine Rev. 16:370-389). Several of these familiescontain distinct genes, many of which are expressed in different tissuesas splice variants. Within PDE families, there are multiple isozymes andmultiple splice variants of these isozymes (Conti, M. and S.-L. C. Jin(1999) Prog. Nucleic Acid Res. Mol. Biol. 63:1-38). The existence ofmultiple PDE families, isozymes, and splice variants is an indication ofthe variety and complexity of the regulatory pathways involving cyclicnucleotides (Houslay, M. D. and G. Milligan (1997) Trends Biochem. Sci.22:217-224).

Type 1 PDEs (PDE 1s) are Ca²⁺/calmodulin-dependent and appear to beencoded by at least three different genes, each having at least twodifferent splice variants (Kakkar, R. et al. (1999) Cell Mol. Life Sci.55:1164-1186). PDE1s have been found in the lung, heart, and brain. SomePDE1 isozymes are regulated in vitro byphosphorylation/dephosphorylation. Phosphorylation of these PDE1isozymes decreases the affinity of the enzyme for calmodulin, decreasesPDE activity, and increases steady state levels of cAMP (Kakkar, supra).PDE1s may provide useful therapeutic targets for disorders of thecentral nervous system, and the cardiovascular and immune systems due tothe involvement of PDE1s in both cyclic nucleotide and calcium signaling(Perry, M. J. and G. A. Higgs (1998) Curr. Opin. Chem. Biol. 2:472-481).

PDE2s are cGMP-stimulated PDEs that have been found in the cerebellum,neocortex, heart, kidney, lung, pulmonary artery, and skeletal muscle(Sadhu, K. et al. (1999) J. Histochem. Cytochem. 47:895-906). PDE2s arethought to mediate the effects of cAMP on catecholamine secretion,participate in the regulation of aldosterone (Beavo, supra), and play arole in olfactory signal transduction (Juilfs, D. M. et al. (1997) Proc.Natl. Acad. Sci. USA 94:3388-3395).

PDE3s have high affinity for both cGMP and cAMP, and so these cyclicnucleotides act as competitive substrates for PDE3s. PDE3s play roles instimulating myocardial contractility, inhibiting platelet aggregation,relaxing vascular and airway smooth muscle, inhibiting proliferation ofT-lymphocytes and cultured vascular smooth muscle cells, and regulatingcatecholamine-induced release of free fatty acids from adipose tissue.The PDE3 family of phosphodiesterases are sensitive to specificinhibitors such as cilostamide, enoximone, and lixazinone. Isozymes ofPDE3 can be regulated by cAMP-dependent protein kinase, or byinsulin-dependent kinases (Degerman, E. et al. (1997) J. Biol. Chem.272:6823-6826).

PDE4s are specific for cAMP; are localized to airway smooth muscle, thevascular endothelium, and all inflammatory cells; and can be activatedby cAMP-dependent phosphorylation. Since elevation of cAMP levels canlead to suppression of inflammatory cell activation and to relaxation ofbronchial smooth muscle, PDE4s have been studied extensively as possibletargets for novel anti-inflammatory agents, with special emphasis placedon the discovery of asthma treatments. PDE4 inhibitors are currentlyundergoing clinical trials as treatments for asthma, chronic obstructivepulmonary disease, and atopic eczema. All four known isozymes of PDE4are susceptible to the inhibitor rolipram, a compound which has beenshown to improve behavioral memory in mice (Barad, M. et al. (1998)Proc. Natl. Acad. Sci. USA 95:15020-15025). PDE4 inhibitors have alsobeen studied as possible therapeutic agents against acute lung injury,endotoxemia, rheumatoid arthritis, multiple sclerosis, and variousneurological and gastrointestinal indications (Doherty, A. M. (1999)Curr. Opin. Chem. Biol. 3:466-473).

PDE5 is highly selective for cGMP as a substrate (Turko, I. V. et al.(1998) Biochemistry 37:42004205), and has two allosteric cGMP-specificbinding sites (McAllister-Lucas, L. M. et al. (1995) J. Biol. Chem.270:30671-30679). Binding of cGMP to these allosteric binding sitesseems to be important for phosphorylation of PDE5 by cGMP-dependentprotein kinase rather than for direct regulation of catalytic activity.High levels of PDE5 are found in vascular smooth muscle, platelets,lung, and kidney. The inhibitor zaprinast is effective against PDE5 andPDE 1s. Modification of zaprinast to provide specificity against PDE5has resulted in sildenafil (VIAGRA; Pfizer, Inc., New York N.Y.), atreatment for male erectile dysfunction (Terrett, N. et al. (1996)Bioorg. Med. Chem. Lett. 6:1819-1824). Inhibitors of PDE5 are currentlybeing studied as agents for cardiovascular therapy (Perry, M. J. and G.A. Higgs (1998) Curr. Opin. Chem. Biol. 2:472-481).

PDE6s, the photoreceptor cyclic nucleotide phosphodiesterases, arecrucial components of the phototransduction cascade. In association withthe G-protein transducin, PDE6s hydrolyze cGMP to regulate cGMP-gatedcation channels in photoreceptor membranes. In addition to thecGMP-binding active site, PDE6s also have two high-affinity cGMP-bindingsites which are thought to play a regulatory role in PDE6 function(Artemyev, N. O. et al. (1998) Methods 14:93-104). Defects in PDE6s havebeen associated with retinal disease. Retinal degeneration in the rdmouse (Yan, W. et al. (1998) Invest. Opthalmol. Vis. Sci. 39:2529-2536),autosomal recessive retinitis pigmentosa in humans (Danciger, M. et al.(1995) Genomics 30:1-7), and rod/cone dysplasia 1 in Irish Setter dogs(Suber, M. L. et al. (1993) Proc. Natl. Acad. Sci. USA 90:3968-3972)have been attributed to mutations in the PDE6B gene.

The PDE7 family of PDEs consists of only one known member havingmultiple splice variants (Bloom, T. J. and J. A. Beavo (1996) Proc.Natl. Acad. Sci. USA 93:14188-14192). PDE7s are cAMP specific, butlittle else is known about their physiological function. Although mRNAsencoding PDE7s are found in skeletal muscle, heart, brain, lung, kidney,and pancreas, expression of PDE7 proteins is restricted to specifictissue types (Han, P. et al. (1997) J. Biol. Chem. 272:16152-16157;Perry, M. J. and G. A. Higgs (1998) Curr. Opin. Chem. Biol. 2:472-481).PDE7s are very closely related to the PDE4 family; however, PDE7s arenot inhibited by rolipram, a specific inhibitor of PDE4s (Beavo, supra).

PDE8s are cAMP specific, and are closely related to the PDE4 family.PDE8s are expressed in thyroid gland, testis, eye, liver, skeletalmuscle, heart, kidney, ovary, and brain. The cAMP-hydrolyzing activityof PDE8s is not inhibited by the PDE inhibitors rolipram, vinpocetine,milrinone, IBMX (3-isobutyl-1-methylxanthine), or zaprinast, but PDE8sare inhibited by dipyridamole (Fisher, D. A. et al. (1998) Biochem.Biophys. Res. Commun. 246:570-577; Hayashi, M. et al. (1998) Biochem.Biophys. Res. Commun. 250:751-756; Soderling, S. H. et al. (1998) Proc.Natl. Acad. Sci. USA 95:8991-8996).

PDE9s are cGMP specific and most closely resemble the PDE8 family ofPDEs. PDE9s are expressed in kidney, liver, lung, brain, spleen, andsmall intestine. PDE9s are not inhibited by sildenafil (VIAGRA; Pfizer,Inc., New York N.Y.), rolipram, vinpocetine, dipyridamole, or IBMX(3-isobutyl-1-methylxanthine), but they are sensitive to the PDE5inhibitor zaprinast (Fisher, D. A. et al. (1998) J. Biol. Chem.273:15559-15564; Soderling, S. H. et al. (1998) J. Biol. Chem.273:15553-15558).

PDE10s are dual-substrate PDEs, hydrolyzing both cAMP and cGMP. PDE10sare expressed in brain, thyroid, and testis. (Soderling, S. H. et al.(1999) Proc. Natl. Acad. Sci. USA 96:7071-7076; Fujishige, K. et al.(1999) J. Biol. Chem. 274:18438-18445; Loughney, K. et al (1999) Gene234:109-117).

Cyclic Nucleotide Phosphodiesterase Structure

PDEs are composed of a catalytic domain of about 270-300 amino acids, anN-terminal regulatory domain responsible for binding cofactors, and, insome cases, a hydrophilic C-terminal domain of unknown function (Conti,M. and S.-L. C. Jin (1999) Prog. Nucleic Acid Res. Mol. Biol. 63:1-38).A conserved, putative zinc-binding motif has been identified in thecatalytic domain of all PDEs. N-terminal regulatory domains includenon-catalytic cGMP-binding domains in PDE2s, PDE5s, and PDE6s;calmodulin-binding domains in PDE1s; and domains containingphosphorylation sites in PDE3s and PDE4s. In PDE5, the N-terminalcGMP-binding domain spans about 380 amino acid residues and comprisestandem repeats of a conserved sequence motif (McAllister-Lucas, L. M. etal. (1993) J. Biol. Chem. 268:22863-22873). This motif has been shown bymutagenesis to be important for cGMP binding (Turko, I. V. et al. (1996)J. Biol. Chem. 271:22240-22244). PDE families display approximately 30%amino acid identity within the catalytic domain; however, isozymeswithin the same family typically display about 85-95% identity in thisregion (e.g. PDE4A vs PDE4B). Furthermore, within a family there isextensive similarity (>60%) outside the catalytic domain; while acrossfamilies, there is little or no sequence similarity outside this domain.

Cyclic Nucleotide Phosphodiesterases in Disease

Many of the constituent functions of immune and inflammatory responsesare inhibited by agents that increase intracellular levels of cAMP(Verghese, M. W. et al. (1995) Mol. Pharmacol. 47:1164-1171). A varietyof diseases have been attributed to increased PDE activity andassociated with decreased levels of cyclic nucleotides. For example, aform of diabetes insipidus in mice has been associated with increasedPDE4 activity, an increase in low-K_(m) cAMP PDE activity has beenreported in leukocytes of atopic patients, and PDE3 has been associatedwith cardiac disease.

Many inhibitors of PDEs have been identified and have undergone clinicalevaluation (Perry, M. J. and G. A. Higgs (1998) Curr. Opin. Chem. Biol.2:472-481; Torphy, T. J. (1998) Am. J. Respir. Crit. Care Med.157:351-370). PDE3 inhibitors are being developed as antithromboticagents, antihypertensive agents, and as cardiotonic agents useful in thetreatment of congestive heart failure. Rolipram, a PDE4 inhibitor, hasbeen used in the treatment of depression, and other inhibitors of PDE4are undergoing evaluation as anti-inflammatory agents. Rolipram has alsobeen shown to inhibit lipopolysaccharide (LPS) induced TNF-α which hasbeen shown to enhance HIV-1replication in vitro. Therefore, rolipram mayinhibit HIV-1 replication (Angel, J. B. et al. (1995) AIDS 9:1137-1144).Additionally, rolipram, based on its ability to suppress the productionof cytokines such as TNF-α and β and interferon γ, has been shown to beeffective in the treatment of encephalomyelitis. Rolipram may also beeffective in treating tardive dyskinesia and was effective in treatingmultiple sclerosis in an experimental animal model (Sommer, N. et al.(1995) Nat. Med. 1:244-248; Sasaki, H. et al. (1995) Eur. J. Pharmacol.282:71-76).

Theophylline is a nonspecific PDE inhibitor used in the treatment ofbronchial asthma and other respiratory diseases. Theophylline isbelieved to act on airway smooth muscle function and in ananti-inflammatory or immunomodulatory capacity in the treatment ofrespiratory diseases (Banner, K. H. and C. P. Page (1995) Eur. Respir.J. 8:996-1000). Pentoxifylline is another nonspecific PDE inhibitor usedin the treatment of intermittent claudication and diabetes-inducedperipheral vascular disease. Pentoxifylline is also known to block TNF-αproduction and may inhibit HIV1 replication (Angel et al., supra).

PDEs have been reported to affect cellular proliferation of a variety ofcell types (Conti et al. (1995) Endocrine Rev. 16:370-389) and have beenimplicated in various cancers. Growth of prostate carcinoma cell linesDU145 and LNCaP was inhibited by delivery of cAMP derivatives and PDEinhibitors (Bang, Y. J. et al. (1994) Proc. Natl. Acad. Sci. USA91:5330-5334). These cells also showed a permanent conversion inphenotype from epithelial to neuronal morphology. It has also beensuggested that PDE inhibitors have the potential to regulate mesangialcell proliferation (Matousovic, K. et al. (1995) J. Clin. Invest.96:401-410) and lymphocyte proliferation (Joulain, C. et al. (1995) J.Lipid Mediat. Cell Signal. 11:63-79). A cancer treatment has beendescribed that involves intracellular delivery of PDEs to particularcellular compartments of tumors, resulting in cell death (Deonarain, M.P. and A. A. Epenetos (1994) Br. J. Cancer 70:786-794).

The discovery of new phosphodiesterases and the polynucleotides encodingthem satisfies a need in the art by providing new compositions which areuseful in the diagnosis, prevention, and treatment of eye, neurological,cardiovascular, cell proliferative, and autoimmune/inflammatorydisorders, and in the assessment of the effects of exogenous compoundson the expression of nucleic acid and amino acid sequences ofphosphodiesterases.

SUMMARY OF THE INVENTION

The invention features purified polypeptides, phosphodiesterases,referred to collectively as “HPDE” and individually as “HPDE-1,”“HPDE-2,” and “HPDE-3.” In one aspect, the invention provides anisolated polypeptide comprising an amino acid sequence selected from thegroup consisting of a) an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3, b) a naturally occurring amino acidsequence having at least 90% sequence identity to an amino acid sequenceselected from the group consisting of SEQ ID NO:1-3, c) a biologicallyactive fragment of an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3, and d) an immunogenic fragment of an aminoacid sequence selected from the group consisting of SEQ ID NO:1-3. Inone alternative, the invention provides an isolated polypeptidecomprising the amino acid sequence of SEQ ID NO:1-3.

The invention further provides an isolated polynucleotide encoding apolypeptide comprising an amino acid sequence selected from the groupconsisting of a) an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3, b) a naturally occurring amino acidsequence having at least 90% sequence identity to an amino acid sequenceselected from the group consisting of SEQ ID NO:1-3, c) a biologicallyactive fragment of an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3, and d) an immunogenic fragment of an aminoacid sequence selected from the group consisting of SEQ ID NO:1-3. Inone alternative, the polynucleotide encodes a polypeptide selected fromthe group consisting of SEQ ID NO:1-3. In another alternative, thepolynucleotide is selected from the group consisting of SEQ ID NO:4-6.

Additionally, the invention provides a recombinant polynucleotidecomprising a promoter sequence operably linked to a polynucleotideencoding a polypeptide comprising an amino acid sequence selected fromthe group consisting of a) an amino acid sequence selected from thegroup consisting of SEQ ID NO:1-3, b) a naturally occurring amino acidsequence having at least 90% sequence identity to an amino acid sequenceselected from the group consisting of SEQ ID NO:1-3, c) a biologicallyactive fragment of an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3, and d) an immunogenic fragment of an aminoacid sequence selected from the group consisting of SEQ ID NO:1-3. Inone alternative, the invention provides a cell transformed with therecombinant polynucleotide. In another alternative, the inventionprovides a transgenic organism comprising the recombinantpolynucleotide.

The invention also provides a method for producing a polypeptidecomprising an amino acid sequence selected from the group consisting ofa) an amino acid sequence selected from the group consisting of SEQ IDNO:1-3, b) a naturally occurring amino acid sequence having at least 90%sequence identity to an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3, c) a biologically active fragment of anamino acid sequence selected from the group consisting of SEQ ID NO:1-3,and d) an immunogenic fragment of an amino acid sequence selected fromthe group consisting of SEQ ID NO:1-3. The method comprises a) culturinga cell under conditions suitable for expression of the polypeptide,wherein said cell is transformed with a recombinant polynucleotidecomprising a promoter sequence operably linked to a polynucleotideencoding the polypeptide, and b) recovering the polypeptide soexpressed.

Additionally, the invention provides an isolated antibody whichspecifically binds to a polypeptide comprising an amino acid sequenceselected from the group consisting of a) an amino acid sequence selectedfrom the group consisting of SEQ ID NO:1-3, b) a naturally occurringamino acid sequence having at least 90% sequence identity to an aminoacid sequence selected from the group consisting of SEQ ID NO:1-3, c) abiologically active fragment of an amino acid sequence selected from thegroup consisting of SEQ ID NO:1-3, and d) an immunogenic fragment of anamino acid sequence selected from the group consisting of SEQ ID NO:1-3.

The invention further provides an isolated polynucleotide comprising apolynucleotide sequence selected from the group consisting of a) apolynucleotide sequence selected from the group consisting of SEQ IDNO:4-6, b) a naturally occurring polynucleotide sequence having at least90% sequence identity to a polynucleotide sequence selected from thegroup consisting of SEQ ID NO:4-6, c) a polynucleotide sequencecomplementary to a), d) a polynucleotide sequence complementary to b),and e) an RNA equivalent of a)-d). In one alternative, thepolynucleotide comprises at least 60 contiguous nucleotides.

Additionally, the invention provides a method for detecting a targetpolynucleotide in a sample, said target polynucleotide having a sequenceof a polynucleotide comprising a polynucleotide sequence selected fromthe group consisting of a) a polynucleotide sequence selected from thegroup consisting of SEQ ID NO:4-6, b) a naturally occurringpolynucleotide sequence having at least 90% sequence identity to apolynucleotide sequence selected from the group consisting of SEQ IDNO:4-6, c) a polynucleotide sequence complementary to a), d) apolynucleotide sequence complementary to b), and e) an RNA equivalent ofa)-d). The method comprises a) hybridizing the sample with a probecomprising at least 20 contiguous nucleotides comprising a sequencecomplementary to said target polynucleotide in the sample, and whichprobe specifically hybridizes to said target polynucleotide, underconditions whereby a hybridization complex is formed between said probeand said target polynucleotide or fragments thereof, and b) detectingthe presence or absence of said hybridization complex, and optionally,if present, the amount thereof. In one alternative, the probe comprisesat least 60 contiguous nucleotides.

The invention further provides a method for detecting a targetpolynucleotide in a sample, said target polynucleotide having a sequenceof a polynucleotide comprising a polynucleotide sequence selected fromthe group consisting of a) a polynucleotide sequence selected from thegroup consisting of SEQ ID NO:4-6, b) a naturally occurringpolynucleotide sequence having at least 90% sequence identity to apolynucleotide sequence selected from the group consisting of SEQ IDNO:4-6, c) a polynucleotide sequence complementary to a), d) apolynucleotide sequence complementary to b), and e) an RNA equivalent ofa)-d). The method comprises a) amplifying said target polynucleotide orfragment thereof using polymerase chain reaction amplification, and b)detecting the presence or absence of said amplified targetpolynucleotide or fragment thereof, and, optionally, if present, theamount thereof.

The invention further provides a composition comprising an effectiveamount of a polypeptide comprising an amino acid sequence selected fromthe group consisting of a) an amino acid sequence selected from thegroup consisting of SEQ ID NO:1-3, b) a naturally occurring amino acidsequence having at least 90% sequence identity to an amino acid sequenceselected from the group consisting of SEQ ID NO:1-3, c) a biologicallyactive fragment of an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3, and d) an immunogenic fragment of an aminoacid sequence selected from the group consisting of SEQ ID NO:1-3, and apharmaceutically acceptable excipient. In one embodiment, thecomposition comprises an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3. The invention additionally provides amethod of treating a disease or condition associated with decreasedexpression of functional HPDE, comprising administering to a patient inneed of such treatment the composition.

The invention also provides a method for screening a compound foreffectiveness as an agonist of a polypeptide comprising an amino acidsequence selected from the group consisting of a) an amino acid sequenceselected from the group consisting of SEQ ID NO:1-3, b) a naturallyoccurring amino acid sequence having at least 90% sequence identity toan amino acid sequence selected from the group consisting of SEQ IDNO:1-3, c) a biologically active fragment of an amino acid sequenceselected from the group consisting of SEQ ID NO:1-3, and d) animmunogenic fragment of an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3. The method comprises a) exposing a samplecomprising the polypeptide to a compound, and b) detecting agonistactivity in the sample. In one alternative, the invention provides acomposition comprising an agonist compound identified by the method anda pharmaceutically acceptable excipient. In another alternative, theinvention provides a method of treating a disease or conditionassociated with decreased expression of functional HPDE, comprisingadministering to a patient in need of such treatment the composition.

Additionally, the invention provides a method for screening a compoundfor effectiveness as an antagonist of a polypeptide comprising an aminoacid sequence selected from the group consisting of a) an amino acidsequence selected from the group consisting of SEQ ID NO:1-3, b) anaturally occurring amino acid sequence having at least 90% sequenceidentity to an amino acid sequence selected from the group consisting ofSEQ ID NO:1-3, c) a biologically active fragment of an amino acidsequence selected from the group consisting of SEQ ID NO:1-3, and d) animmunogenic fragment of an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3. The method comprises a) exposing a samplecomprising the polypeptide to a compound, and b) detecting antagonistactivity in the sample. In one alternative, the invention provides acomposition comprising an antagonist compound identified by the methodand a pharmaceutically acceptable excipient. In another alternative, theinvention provides a method of treating a disease or conditionassociated with overexpression of functional HPDE, comprisingadministering to a patient in need of such treatment the composition.

The invention further provides a method of screening for a compound thatspecifically binds to a polypeptide comprising an amino acid sequenceselected from the group consisting of a) an amino acid sequence selectedfrom the group consisting of SEQ ID NO:1-3, b) a naturally occurringamino acid sequence having at least 90% sequence identity to an aminoacid sequence selected from the group consisting of SEQ ID NO:1-3, c) abiologically active fragment of an amino acid sequence selected from thegroup consisting of SEQ ID NO:1-3, and d) an immunogenic fragment of anamino acid sequence selected from the group consisting of SEQ ID NO:1-3.The method comprises a) combining the polypeptide with at least one testcompound under suitable conditions, and b) detecting binding of thepolypeptide to the test compound, thereby identifying a compound thatspecifically binds to the polypeptide.

The invention further provides a method of screening for a compound thatmodulates the activity of a polypeptide comprising an amino acidsequence selected from the group consisting of a) an amino acid sequenceselected from the group consisting of SEQ ID NO:1-3, b) a naturallyoccurring amino acid sequence having at least 90% sequence identity toan amino acid sequence selected from the group consisting of SEQ IDNO:1-3, c) a biologically active fragment of an amino acid sequenceselected from the group consisting of SEQ ID NO:1-3, and d) animmunogenic fragment of an amino acid sequence selected from the groupconsisting of SEQ ID NO:1-3. The method comprises a) combining thepolypeptide with at least one test compound under conditions permissivefor the activity of the polypeptide, b) assessing the activity of thepolypeptide in the presence of the test compound, and c) comparing theactivity of the polypeptide in the presence of the test compound withthe activity of the polypeptide in the absence of the test compound,wherein a change in the activity of the polypeptide in the presence ofthe test compound is indicative of a compound that modulates theactivity of the polypeptide.

The invention further provides a method for screening a compound foreffectiveness in altering expression of a target polynucleotide, whereinsaid target polynucleotide comprises a sequence selected from the groupconsisting of SEQ ID NO:4-6, the method comprising a) exposing a samplecomprising the target polynucleotide to a compound, and b) detectingaltered expression of the target polynucleotide.

The invention further provides a method for assessing toxicity of a testcompound, said method comprising a) treating a biological samplecontaining nucleic acids with the test compound; b) hybridizing thenucleic acids of the treated biological sample with a probe comprisingat least 20 contiguous nucleotides of a polynucleotide comprising apolynucleotide sequence selected from the group consisting of i) apolynucleotide sequence selected from the group consisting of SEQ IDNO:4-6, ii) a naturally occurring polynucleotide sequence having atleast 90% sequence identity to a polynucleotide sequence selected fromthe group consisting of SEQ ID NO:4-6, iii) a polynucleotide sequencecomplementary to i), iv) a polynucleotide sequence complementary to ii),and v) an RNA equivalent of i)-iv). Hybridization occurs underconditions whereby a specific hybridization complex is formed betweensaid probe and a target polynucleotide in the biological sample, saidtarget polynucleotide comprising a polynucleotide sequence selected fromthe group consisting of i) a polynucleotide sequence selected from thegroup consisting of SEQ ID NO:4-6, ii) a naturally occurringpolynucleotide sequence having at least 90% sequence identity to apolynucleotide sequence selected from the group consisting of SEQ IDNO:4-6, iii) a polynucleotide sequence complementary to i), iv) apolynucleotide sequence complementary to ii), and v) an RNA equivalentof i)-iv). Alternatively, the target polynucleotide comprises a fragmentof a polynucleotide sequence selected from the group consisting of i)-v)above; c) quantifying the amount of hybridization complex; and d)comparing the amount of hybridization complex in the treated biologicalsample with the amount of hybridization complex in an untreatedbiological sample, wherein a difference in the amount of hybridizationcomplex in the treated biological sample is indicative of toxicity ofthe test compound.

BRIEF DESCRIPTION OF THE TABLES

Table 1 summarizes the nomenclature for the full length polynucleotideand polypeptide sequences of the present invention.

Table 2 shows the GenBank identification number and annotation of thenearest GenBank homolog for polypeptides of the invention. Theprobability score for the match between each polypeptide and its GenBankhomolog is also shown.

Table 3 shows structural features of polypeptide sequences of theinvention, including predicted motifs and domains, along with themethods, algorithms, and searchable databases used for analysis of thepolypeptides.

Table 4 lists the cDNA fragments which were used to assemblepolynucleotide sequences of the invention, along with selected fragmentsof the polynucleotide sequences.

Table 5 shows the representative cDNA library for polynucleotides of theinvention.

Table 6 provides an appendix which describes the tissues and vectorsused for construction of the cDNA libraries shown in Table 5.

Table 7 shows the tools, programs, and algorithms used to analyze thepolynucleotides and polypeptides of the invention, along with applicabledescriptions, references, and threshold parameters.

DESCRIPTION OF THE INVENTION

Before the present proteins, nucleotide sequences, and methods aredescribed, it is understood that this invention is not limited to theparticular machines, materials and methods described, as these may vary.It is also to be understood that the terminology used herein is for thepurpose of describing particular embodiments only, and is not intendedto limit the scope of the present invention which will be limited onlyby the appended claims.

It must be noted that as used herein and in the appended claims, thesingular forms “a,” “an,” and “the” include plural reference unless thecontext clearly dictates otherwise. Thus, for example, a reference to “ahost cell” includes a plurality of such host cells, and a reference to“an antibody” is a reference to one or more antibodies and equivalentsthereof known to those skilled in the art, and so forth.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meanings as commonly understood by one of ordinary skillin the art to which this invention belongs. Although any machines,materials, and methods similar or equivalent to those described hereincan be used to practice or test the present invention, the preferredmachines, materials and methods are now described. All publicationsmentioned herein are cited for the purpose of describing and disclosingthe cell lines, protocols, reagents and vectors which are reported inthe publications and which might be used in connection with theinvention. Nothing herein is to be construed as an admission that theinvention is not entitled to antedate such disclosure by virtue of priorinvention.

Definitions

“HPDE” refers to the amino acid sequences of substantially purified HPDEobtained from any species, particularly a mammalian species, includingbovine, ovine, porcine, murine, equine, and human, and from any source,whether natural, synthetic, semi-synthetic, or recombinant.

The term “agonist” refers to a molecule which intensifies or mimics thebiological activity of HPDE. Agonists may include proteins, nucleicacids, carbohydrates, small molecules, or any other compound orcomposition which modulates the activity of HPDE either by directlyinteracting with HPDE or by acting on components of the biologicalpathway in which HPDE participates.

An “allelic variant” is an alternative form of the gene encoding HPDE.Allelic variants may result from at least one mutation in the nucleicacid sequence and may result in altered mRNAs or in polypeptides whosestructure or function may or may not be altered. A gene may have none,one, or many allelic variants of its naturally occurring form. Commonmutational changes which give rise to allelic variants are generallyascribed to natural deletions, additions, or substitutions ofnucleotides. Each of these types of changes may occur alone, or incombination with the others, one or more times in a given sequence.

“Altered” nucleic acid sequences encoding HPDE include those sequenceswith deletions, insertions, or substitutions of different nucleotides,resulting in a polypeptide the same as HPDE or a polypeptide with atleast one functional characteristic of HPDE. Included within thisdefinition are polymorphisms which may or may not be readily detectableusing a particular oligonucleotide probe of the polynucleotide encodingHPDE, and improper or unexpected hybridization to allelic variants, witha locus other than the normal chromosomal locus for the polynucleotidesequence encoding HPDE. The encoded protein may also be “altered,” andmay contain deletions, insertions, or substitutions of amino acidresidues which produce a silent change and result in a functionallyequivalent HPDE. Deliberate amino acid substitutions may be made on thebasis of similarity in polarity, charge, solubility, hydrophobicity,hydrophilicity, and/or the amphipathic nature of the residues, as longas the biological or immunological activity of HPDE is retained. Forexample, negatively charged amino acids may include aspartic acid andglutamic acid, and positively charged amino acids may include lysine andarginine. Amino acids with uncharged polar side chains having similarhydrophilicity values may include: asparagine and glutamine; and serineand threonine. Amino acids with uncharged side chains having similarhydrophilicity values may include: leucine, isoleucine, and valine;glycine and alanine; and phenylalanine and tyrosine.

The terms “amino acid” and “amino acid sequence” refer to anoligopeptide, peptide, polypeptide, or protein sequence, or a fragmentof any of these, and to naturally occurring or synthetic molecules.Where “amino acid sequence” is recited to refer to a sequence of anaturally occurring protein molecule, “amino acid sequence” and liketerms are not meant to limit the amino acid sequence to the completenative amino acid sequence associated with the recited protein molecule.

“Amplification” relates to the production of additional copies of anucleic acid sequence. Amplification is generally carried out usingpolymerase chain reaction (PCR) technologies well known in the art.

The term “antagonist” refers to a molecule which inhibits or attenuatesthe biological activity of HPDE. Antagonists may include proteins suchas antibodies, nucleic acids, carbohydrates, small molecules, or anyother compound or composition which modulates the activity of HPDEeither by directly interacting with HPDE or by acting on components ofthe biological pathway in which HPDE participates.

The term “antibody” refers to intact immunoglobulin molecules as well asto fragments thereof, such as Fab, F(ab′)₂, and Fv fragments, which arecapable of binding an epitopic determinant. Antibodies that bind HPDEpolypeptides can be prepared using intact polypeptides or usingfragments containing small peptides of interest as the immunizingantigen. The polypeptide or oligopeptide used to immunize an animal(e.g., a mouse, a rat, or a rabbit) can be derived from the translationof RNA, or synthesized chemically, and can be conjugated to a carrierprotein if desired. Commonly used carriers that are chemically coupledto peptides include bovine serum albumin, thyroglobulin, and keyholelimpet hemocyanin (KLH). The coupled peptide is then used to immunizethe animal.

The term “antigenic determinant” refers to that region of a molecule(i.e., an epitope) that makes contact with a particular antibody. When aprotein or a fragment of a protein is used to immunize a host animal,numerous regions of the protein may induce the production of antibodieswhich bind specifically to antigenic determinants (particular regions orthree-dimensional structures on the protein). An antigenic determinantmay compete with the intact antigen (i.e., the immunogen used to elicitthe immune response) for binding to an antibody.

The term “antisense” refers to any composition capable of base-pairingwith the “sense” (coding) strand of a specific nucleic acid sequence.Antisense compositions may include DNA; RNA; peptide nucleic acid (PNA);oligonucleotides having modified backbone linkages such asphosphorothioates, methylphosphonates, or benzylphosphonates;oligonucleotides having modified sugar groups such as 2′-methoxyethylsugars or 2′-methoxyethoxy sugars; or oligonucleotides having modifiedbases such as 5-methyl cytosine, 2′-deoxyuracil, or7-deaza-2′-deoxyguanosine. Antisense molecules may be produced by anymethod including chemical synthesis or transcription. Once introducedinto a cell, the complementary antisense molecule base-pairs with anaturally occurring nucleic acid sequence produced by the cell to formduplexes which block either transcription or translation. Thedesignation “negative” or “minus” can refer to the antisense strand, andthe designation “positive” or “plus” can refer to the sense strand of areference DNA molecule.

The term “biologically active” refers to a protein having structural,regulatory, or biochemical functions of a naturally occurring molecule.Likewise, “immunologically active” or “immunogenic” refers to thecapability of the natural, recombinant, or synthetic HPDE, or of anyoligopeptide thereof, to induce a specific immune response inappropriate animals or cells and to bind with specific antibodies.

“Complementary” describes the relationship between two single-strandednucleic acid sequences that anneal by base-pairing. For example,5′-AGT-3′ pairs with its complement, 3′-TCA-5′.

A “composition comprising a given polynucleotide sequence” and a“composition comprising a given amino acid sequence” refer broadly toany composition containing the given polynucleotide or amino acidsequence. The composition may comprise a dry formulation or an aqueoussolution. Compositions comprising polynucleotide sequences encoding HPDEor fragments of HPDE may be employed as hybridization probes. The probesmay be stored in freeze-dried form and may be associated with astabilizing agent such as a carbohydrate. In hybridizations, the probemay be deployed in an aqueous solution containing salts (e.g., NaCl),detergents (e.g., sodium dodecyl sulfate; SDS), and other components(e.g., Denhardt's solution, dry milk, salmon sperm DNA, etc.).

“Consensus sequence” refers to a nucleic acid sequence which has beensubjected to repeated DNA sequence analysis to resolve uncalled bases,extended using the XL-PCR kit (Applied Biosystems, Foster City Calif.)in the 5′ and/or the 3′ direction, and resequenced, or which has beenassembled from one or more overlapping cDNA, EST, or genomic DNAfragments using a computer program for fragment assembly, such as theGELVIEW fragment assembly system (GCG, Madison Wis.) or Phrap(University of Washington, Seattle Wash.). Some sequences have been bothextended and assembled to produce the consensus sequence.

“Conservative amino acid substitutions” are those substitutions that arepredicted to least interfere with the properties of the originalprotein, i.e., the structure and especially the function of the proteinis conserved and not significantly changed by such substitutions. Thetable below shows amino acids which may be substituted for an originalamino acid in a protein and which are regarded as conservative aminoacid substitutions.

Original Residue Conservative Substitution Ala Gly, Ser Arg His, Lys AsnAsp, Gln, His Asp Asn, Glu Cys Ala, Ser Gln Asn, Glu, His Glu Asp, Gln,His Gly Ala His Asn, Arg, Gln, Glu Ile Leu, Val Leu Ile, Val Lys Arg,Gln, Glu Met Leu, Ile Phe His, Met, Leu, Trp, Tyr Ser Cys, Thr Thr Ser,Val Trp Phe, Tyr Tyr His, Phe,Trp Val Ile, Leu, Thr

Conservative amino acid substitutions generally maintain (a) thestructure of the polypeptide backbone in the area of the substitution,for example, as a beta sheet or alpha helical conformation, (b) thecharge or hydrophobicity of the molecule at the site of thesubstitution, and/or (c) the bulk of the side chain.

A “deletion” refers to a change in the amino acid or nucleotide sequencethat results in the absence of one or more amino acid residues ornucleotides.

The term “derivative” refers to a chemically modified polynucleotide orpolypeptide. Chemical modifications of a polynucleotide can include, forexample, replacement of hydrogen by an alkyl, acyl, hydroxyl, or aminogroup. A derivative polynucleotide encodes a polypeptide which retainsat least one biological or immunological function of the naturalmolecule. A derivative polypeptide is one modified by glycosylation,pegylation, or any similar process that retains at least one biologicalor immunological function of the polypeptide from which it was derived.

A “detectable label” refers to a reporter molecule or enzyme that iscapable of generating a measurable signal and is covalently ornoncovalently joined to a polynucleotide or polypeptide.

A “fragment” is a unique portion of HPDE or the polynucleotide encodingHPDE which is identical in sequence to but shorter in length than theparent sequence. A fragment may comprise up to the entire length of thedefined sequence, minus one nucleotide/amino acid residue. For example,a fragment may comprise from 5 to 1000 contiguous nucleotides or aminoacid residues. A fragment used as a probe, primer, antigen, therapeuticmolecule, or for other purposes, may be at least 5, 10, 15, 16, 20, 25,30, 40, 50, 60, 75, 100, 150, 250 or at least 500 contiguous nucleotidesor amino acid residues in length. Fragments may be preferentiallyselected from certain regions of a molecule. For example, a polypeptidefragment may comprise a certain length of contiguous amino acidsselected from the first 250 or 500 amino acids (or first 25% or 50%) ofa polypeptide as shown in a certain defined sequence. Clearly theselengths are exemplary, and any length that is supported by thespecification, including the Sequence Listing, tables, and figures, maybe encompassed by the present embodiments.

A fragment of SEQ ID NO:4-6 comprises a region of unique polynucleotidesequence that specifically identifies SEQ ID NO:4-6, for example, asdistinct from any other sequence in the genome from which the fragmentwas obtained. A fragment of SEQ ID NO:4-6 is useful, for example, inhybridization and amplification technologies and in analogous methodsthat distinguish SEQ ID NO:4-6 from related polynucleotide sequences.The precise length of a fragment of SEQ ID NO:4-6 and the region of SEQID NO:4-6 to which the fragment corresponds are routinely determinableby one of ordinary skill in the art based on the intended purpose forthe fragment.

A fragment of SEQ ID NO:1-3 is encoded by a fragment of SEQ ID NO:4-6. Afragment of SEQ ID NO:1-3 comprises a region of unique amino acidsequence that specifically identifies SEQ ID NO:1-3. For example, afragment of SEQ ID NO:1-3 is useful as an immunogenic peptide for thedevelopment of antibodies that specifically recognize SEQ ID NO:1-3. Theprecise length of a fragment of SEQ ID NO:1-3 and the region of SEQ IDNO:1-3 to which the fragment corresponds are routinely determinable byone of ordinary skill in the art based on the intended purpose for thefragment.

A “full length” polynucleotide sequence is one containing at least atranslation initiation codon (e.g., methionine) followed by an openreading frame and a translation termination codon. A “full length”polynucleotide sequence encodes a “full length” polypeptide sequence.

“Homology” refers to sequence similarity or, interchangeably, sequenceidentity, between two or more polynucleotide sequences or two or morepolypeptide sequences.

The terms “percent identity” and “% identity,” as applied topolynucleotide sequences, refer to the percentage of residue matchesbetween at least two polynucleotide sequences aligned using astandardized algorithm. Such an algorithm may insert, in a standardizedand reproducible way, gaps in the sequences being compared in order tooptimize alignment between two sequences, and therefore achieve a moremeaningful comparison of the two sequences.

Percent identity between polynucleotide sequences may be determinedusing the default parameters of the CLUSTAL V algorithm as incorporatedinto the MEGALIGN version 3.12e sequence alignment program. This programis part of the LASERGENE software package, a suite of molecularbiological analysis programs (DNASTAR, Madison Wis.). CLUSTAL V isdescribed in Higgins, D. G. and P. M. Sharp (1989) CABIOS 5:151-153 andin Higgins, D. G. et al. (1992) CABIOS 8:189-191. For pairwisealignments of polynucleotide sequences, the default parameters are setas follows: Ktuple=2, gap penalty=5, window=4, and “diagonals saved”=4.The “weighted” residue weight table is selected as the default. Percentidentity is reported by CLUSTAL V as the “percent similarity” betweenaligned polynucleotide sequences.

Alternatively, a suite of commonly used and freely available sequencecomparison algorithms is provided by the National Center forBiotechnology Information (NCBI) Basic Local Alignment Search Tool(BLAST) (Altschul, S. F. et al. (1990) J. Mol. Biol. 215:403-410), whichis available from several sources, including the NCBI, Bethesda, Md.,and on the Internet at http://www.ncbi.nlm.nih.gov/BLAST/. The BLASTsoftware suite includes various sequence analysis programs including“blastn,” that is used to align a known polynucleotide sequence withother polynucleotide sequences from a variety of databases. Alsoavailable is a tool called “BLAST 2 Sequences” that is used for directpairwise comparison of two nucleotide sequences. “BLAST 2 Sequences” canbe accessed and used interactively athttp://www.ncbi.nlm.nih.gov/gorf/b12.html. The “BLAST 2 Sequences” toolcan be used for both blastn and blastp (discussed below). BLAST programsare commonly used with gap and other parameters set to default settings.For example, to compare two nucleotide sequences, one may use blastnwith the “BLAST 2 Sequences” tool Version 2.0.12 (Apr.21 2000) set atdefault parameters. Such default parameters may be, for example:

Matrix: BLOSUM62

Reward for match: 1

Penalty for mismatch: −2

Open Gap: 5 and Extension Gap: 2 penalties

Gap x drop-off: 50

Expect: 10

Word Size: 11

Filter: on

Percent identity may be measured over the length of an entire definedsequence, for example, as defined by a particular SEQ ID number, or maybe measured over a shorter length, for example, over the length of afragment taken from a larger, defined sequence, for instance, a fragmentof at least 20, at least 30, at least 40, at least 50, at least 70, atleast 100, or at least 200 contiguous nucleotides. Such lengths areexemplary only, and it is understood that any fragment length supportedby the sequences shown herein, in the tables, figures, or SequenceListing, may be used to describe a length over which percentage identitymay be measured.

Nucleic acid sequences that do not show a high degree of identity maynevertheless encode similar amino acid sequences due to the degeneracyof the genetic code. It is understood that changes in a nucleic acidsequence can be made using this degeneracy to produce multiple nucleicacid sequences that all encode substantially the same protein.

The phrases “percent identity” and “% identity,” as applied topolypeptide sequences, refer to the percentage of residue matchesbetween at least two polypeptide sequences aligned using a standardizedalgorithm. Methods of polypeptide sequence alignment are well-known.Some alignment methods take into account conservative amino acidsubstitutions. Such conservative substitutions, explained in more detailabove, generally preserve the charge and hydrophobicity at the site ofsubstitution, thus preserving the structure (and therefore function) ofthe polypeptide.

Percent identity between polypeptide sequences may be determined usingthe default parameters of the CLUSTAL V algorithm as incorporated intothe MEGALIGN version 3.12e sequence alignment program (described andreferenced above). For pairwise alignments of polypeptide sequencesusing CLUSTAL V, the default parameters are set as follows: Ktuple=1,gap penalty=3, window=5, and “diagonals saved”=5. The PAM250 matrix isselected as the default residue weight table. As with polynucleotidealignments, the percent identity is reported by CLUSTAL V as the“percent similarity” between aligned polypeptide sequence pairs.

Alternatively the NCBI BLAST software suite may be used. For example,for a pairwise comparison of two polypeptide sequences, one may use the“BLAST 2 Sequences” tool Version 2.0.12 (Apr. 21, 2000) with blastp setat default parameters. Such default parameters may be, for example:

Matrix: BLOSUM62

Open Gap: II and Extension Gap: 1 penalties

Gap x drop-off: 50

Expect: 10

Word Size: 3

Filter: on

Percent identity may be measured over the length of an entire definedpolypeptide sequence, for example, as defined by a particular SEQ IDnumber, or may be measured over a shorter length, for example, over thelength of a fragment taken from a larger, defined polypeptide sequence,for instance, a fragment of at least 15, at least 20, at least 30, atleast 40, at least 50, at least 70 or at least 150 contiguous residues.Such lengths are exemplary only, and it is understood that any fragmentlength supported by the sequences shown herein, in the tables, figuresor Sequence Listing, may be used to describe a length over whichpercentage identity may be measured.

“Human artificial chromosomes” (HACs) are linear microchromosomes whichmay contain DNA sequences of about 6 kb to 10 Mb in size and whichcontain all of the elements required for chromosome replication,segregation and maintenance.

The term “humanized antibody” refers to an antibody molecule in whichthe amino acid sequence in the non-antigen binding regions has beenaltered so that the antibody more closely resembles a human antibody,and still retains its original binding ability.

“Hybridization” refers to the process by which a polynucleotide strandanneals with a complementary strand through base pairing under definedhybridization conditions. Specific hybridization is an indication thattwo nucleic acid sequences share a high degree of complementarity.Specific hybridization complexes form under permissive annealingconditions and remain hybridized after the “washing” step(s). Thewashing step(s) is particularly important in determining the stringencyof the hybridization process, with more stringent conditions allowingless non-specific binding, i.e., binding between pairs of nucleic acidstrands that are not perfectly matched. Permissive conditions forannealing of nucleic acid sequences are routinely determinable by one ofordinary skill in the art and may be consistent among hybridizationexperiments, whereas wash conditions may be varied among experiments toachieve the desired stringency, and therefore hybridization specificity.Permissive annealing conditions occur, for example, at 68° C. in thepresence of about 6×SSC, about 1% (w/v) SDS, and about 100 μg/mlsheared, denatured salmon sperm DNA.

Generally, stringency of hybridization is expressed, in part, withreference to the temperature under which the wash step is carried out.Such wash temperatures are typically selected to be about 5° C. to 20°C. lower than the thermal melting point (T_(m)) for the specificsequence at a defined ionic strength and pH. The T_(m) is thetemperature (under defined ionic strength and pH) at which 50% of thetarget sequence hybridizes to a perfectly matched probe. An equation forcalculating T_(m) and conditions for nucleic acid hybridization are wellknown and can be found in Sambrook, J. et al. (1989) Molecular Cloning:A Laboratory Manual, 2^(nd) ed., vol. 1-3, Cold Spring Harbor Press,Plainview N.Y.; specifically see volume 2, chapter 9.

High stringency conditions for hybridization between polynucleotides ofthe present invention include wash conditions of 68° C. in the presenceof about 0.2×SSC and about 0.1% SDS, for 1 hour. Alternatively,temperatures of about 65° C., 60° C., 55° C., or 42° C. may be used. SSCconcentration may be varied from about 0.1 to 2×SSC, with SDS beingpresent at about 0.1%. Typically, blocking reagents are used to blocknon-specific hybridization. Such blocking reagents include, forinstance, sheared and denatured salmon sperm DNA at about 100-200 μg/ml.Organic solvent, such as formamide at a concentration of about 35-50%v/v, may also be used under particular circumstances, such as forRNA:DNA hybridizations. Useful variations on these wash conditions willbe readily apparent to those of ordinary skill in the art.Hybridization, particularly under high stringency conditions, may besuggestive of evolutionary similarity between the nucleotides. Suchsimilarity is strongly indicative of a similar role for the nucleotidesand their encoded polypeptides.

The term “hybridization complex” refers to a complex formed between twonucleic acid sequences by virtue of the formation of hydrogen bondsbetween complementary bases. A hybridization complex may be formed insolution (e.g., C₀t or R₀t analysis) or formed between one nucleic acidsequence present in solution and another nucleic acid sequenceimmobilized on a solid support (e.g., paper, membranes, filters, chips,pins or glass slides, or any other appropriate substrate to which cellsor their nucleic acids have been fixed).

The words “insertion” and “addition” refer to changes in an amino acidor nucleotide sequence resulting in the addition of one or more aminoacid residues or nucleotides, respectively.

“Immune response” can refer to conditions associated with inflammation,trauma, immune disorders, or infectious or genetic disease, etc. Theseconditions can be characterized by expression of various factors, e.g.,cytokines, chemokines, and other signaling molecules, which may affectcellular and systemic defense systems.

An “immunogenic fragment” is a polypeptide or oligopeptide fragment ofHPDE which is capable of eliciting an immune response when introducedinto a living organism, for example, a mammal. The term “immunogenicfragment” also includes any polypeptide or oligopeptide fragment of HPDEwhich is useful in any of the antibody production methods disclosedherein or known in the art.

The term “microarray” refers to an arrangement of a plurality ofpolynucleotides, polypeptides, or other chemical compounds on asubstrate.

The terms “element” and “array element” refer to a polynucleotide,polypeptide, or other chemical compound having a unique and definedposition on a microarray.

The term “modulate” refers to a change in the activity of HPDE. Forexample, modulation may cause an increase or a decrease in proteinactivity, binding characteristics, or any other biological, functional,or immunological properties of HPDE.

The phrases “nucleic acid” and “nucleic acid sequence” refer to anucleotide, oligonucleotide, polynucleotide, or any fragment thereof.These phrases also refer to DNA or RNA of genomic or synthetic originwhich may be single-stranded or double-stranded and may represent thesense or the antisense strand, to peptide nucleic acid (PNA), or to anyDNA-like or RNA-like material.

“Operably linked” refers to the situation in which a first nucleic acidsequence is placed in a functional relationship with a second nucleicacid sequence. For instance, a promoter is operably linked to a codingsequence if the promoter affects the transcription or expression of thecoding sequence. Operably linked DNA sequences may be in close proximityor contiguous and, where necessary to join two protein coding regions,in the same reading frame.

“Peptide nucleic acid” (PNA) refers to an antisense molecule oranti-gene agent which comprises an oligonucleotide of at least about 5nucleotides in length linked to a peptide backbone of amino acidresidues ending in lysine. The terminal lysine confers solubility to thecomposition. PNAs preferentially bind complementary single stranded DNAor RNA and stop transcript elongation, and may be pegylated to extendtheir lifespan in the cell.

“Post-translational modification” of an HPDE may involve lipidation,glycosylation, phosphorylation, acetylation, racemization, proteolyticcleavage, and other modifications known in the art. These processes mayoccur synthetically or biochemically. Biochemical modifications willvary by cell type depending on the enzymatic milieu of HPDE.

“Probe” refers to nucleic acid sequences encoding HPDE, theircomplements, or fragments thereof, which are used to detect identical,allelic or related nucleic acid sequences. Probes are isolatedoligonucleotides or polynucleotides attached to a detectable label orreporter molecule. Typical labels include radioactive isotopes, ligands,chemiluminescent agents, and enzymes. “Primers” are short nucleic acids,usually DNA oligonucleotides, which may be annealed to a targetpolynucleotide by complementary base-pairing. The primer may then beextended along the target DNA strand by a DNA polymerase enzyme. Primerpairs can be used for amplification (and identification) of a nucleicacid sequence, e.g., by the polymerase chain reaction (PCR).

Probes and primers as used in the present invention typically compriseat least 15 contiguous nucleotides of a known sequence. In order toenhance specificity, longer probes and primers may also be employed,such as probes and primers that comprise at least 20, 25, 30, 40, 50,60, 70, 80, 90, 100, or at least 150 consecutive nucleotides of thedisclosed nucleic acid sequences. Probes and primers may be considerablylonger than these examples, and it is understood that any lengthsupported by the specification, including the tables, figures, andSequence Listing, may be used.

Methods for preparing and using probes and primers are described in thereferences, for example Sambrook, J. et al. (1989) Molecular Cloning: ALaboratory Manual, 2^(nd) ed., vol. 1-3, Cold Spring Harbor Press,Plainview N.Y.; Ausubel, F. M. et al. (1987) Current Protocols inMolecular Biology, Greene Publ. Assoc. & Wiley-Intersciences, New YorkN.Y.; Innis, M. et al. (1990) PCR Protocols, A Guide to Methods andApplications, Academic Press, San Diego Calif. PCR primer pairs can bederived from a known sequence, for example, by using computer programsintended for that purpose such as Primer (Version 0.5, 1991, WhiteheadInstitute for Biomedical Research, Cambridge Mass.).

Oligonucleotides for use as primers are selected using software known inthe art for such purpose. For example, OLIGO 4.06 software is useful forthe selection of PCR primer pairs of up to 100 nucleotides each, and forthe analysis of oligonucleotides and larger polynucleotides of up to5,000 nucleotides from an input polynucleotide sequence of up to 32kilobases. Similar primer selection programs have incorporatedadditional features for expanded capabilities. For example, the PrimOUprimer selection program (available to the public from the Genome Centerat University of Texas South West Medical Center, Dallas Tex.) iscapable of choosing specific primers from megabase sequences and is thususeful for designing primers on a genome-wide scope. The Primer3 primerselection program (available to the public from the WhiteheadInstitute/MIT Center for Genome Research, Cambridge Mass.) allows theuser to input a “mispriming library,” in which sequences to avoid asprimer binding sites are user-specified. Primer3 is useful, inparticular, for the selection of oligonucleotides for microarrays. (Thesource code for the latter two primer selection programs may also beobtained from their respective sources and modified to meet the user'sspecific needs.) The PrimeGen program (available to the public from theUK Human Genome Mapping Project Resource Centre, Cambridge UK) designsprimers based on multiple sequence alignments, thereby allowingselection of primers that hybridize to either the most conserved orleast conserved regions of aligned nucleic acid sequences. Hence, thisprogram is useful for identification of both unique and conservedoligonucleotides and polynucleotide fragments. The oligonucleotides andpolynucleotide fragments identified by any of the above selectionmethods are useful in hybridization technologies, for example, as PCR orsequencing primers, microarray elements, or specific probes to identifyfully or partially complementary polynucleotides in a sample of nucleicacids. Methods of oligonucleotide selection are not limited to thosedescribed above.

A “recombinant nucleic acid” is a sequence that is not naturallyoccurring or has a sequence that is made by an artificial combination oftwo or more otherwise separated segments of sequence. This artificialcombination is often accomplished by chemical synthesis or, morecommonly, by the artificial manipulation of isolated segments of nucleicacids, e.g., by genetic engineering techniques such as those describedin Sambrook, supra. The term recombinant includes nucleic acids thathave been altered solely by addition, substitution, or deletion of aportion of the nucleic acid. Frequently, a recombinant nucleic acid mayinclude a nucleic acid sequence operably linked to a promoter sequence.Such a recombinant nucleic acid may be part of a vector that is used,for example, to transform a cell.

Alternatively, such recombinant nucleic acids may be part of a viralvector, e.g., based on a vaccinia virus, that could be use to vaccinatea mammal wherein the recombinant nucleic acid is expressed, inducing aprotective immunological response in the mammal.

A “regulatory element” refers to a nucleic acid sequence usually derivedfrom untranslated regions of a gene and includes enhancers, promoters,introns, and 5′ and 3′ untranslated regions (UTRs). Regulatory elementsinteract with host or viral proteins which control transcription,translation, or RNA stability.

“Reporter molecules” are chemical or biochemical moieties used forlabeling a nucleic acid, amino acid, or antibody. Reporter moleculesinclude radionuclides; enzymes; fluorescent, chemiluminescent, orchromogenic agents; substrates; cofactors; inhibitors; magneticparticles; and other moieties known in the art.

An “RNA equivalent,” in reference to a DNA sequence, is composed of thesame linear sequence of nucleotides as the reference DNA sequence withthe exception that all occurrences of the nitrogenous base thymine arereplaced with uracil, and the sugar backbone is composed of riboseinstead of deoxyribose.

The term “sample” is used in its broadest sense. A sample suspected ofcontaining HPDE, nucleic acids encoding HPDE, or fragments thereof maycomprise a bodily fluid; an extract from a cell, chromosome, organelle,or membrane isolated from a cell; a cell; genomic DNA, RNA, or cDNA, insolution or bound to a substrate; a tissue; a tissue print; etc.

The terms “specific binding” and “specifically binding” refer to thatinteraction between a protein or peptide and an agonist, an antibody, anantagonist, a small molecule, or any natural or synthetic bindingcomposition. The interaction is dependent upon the presence of aparticular structure of the protein, e.g., the antigenic determinant orepitope, recognized by the binding molecule. For example, if an antibodyis specific for epitope “A,” the presence of a polypeptide comprisingthe epitope A, or the presence of free unlabeled A, in a reactioncontaining free labeled A and the antibody will reduce the amount oflabeled A that binds to the antibody.

The term “substantially purified” refers to nucleic acid or amino acidsequences that are removed from their natural environment and areisolated or separated, and are at least 60% free, preferably at least75% free, and most preferably at least 90% free from other componentswith which they are naturally associated.

A “substitution” refers to the replacement of one or more amino acidresidues or nucleotides by different amino acid residues or nucleotides,respectively.

“Substrate” refers to any suitable rigid or semi-rigid support includingmembranes, filters, chips, slides, wafers, fibers, magnetic ornonmagnetic beads, gels, tubing, plates, polymers, microparticles andcapillaries. The substrate can have a variety of surface forms, such aswells, trenches, pins, channels and pores, to which polynucleotides orpolypeptides are bound.

A “transcript image” refers to the collective pattern of gene expressionby a particular cell type or tissue under given conditions at a giventime.

“Transformation” describes a process by which exogenous DNA isintroduced into a recipient cell. Transformation may occur under naturalor artificial conditions according to various methods well known in theart, and may rely on any known method for the insertion of foreignnucleic acid sequences into a prokaryotic or eukaryotic host cell. Themethod for transformation is selected based on the type of host cellbeing transformed and may include, but is not limited to, bacteriophageor viral infection, electroporation, heat shock, lipofection, andparticle bombardment. The term “transformed cells” includes stablytransformed cells in which the inserted DNA is capable of replicationeither as an autonomously replicating plasmid or as part of the hostchromosome, as well as transiently transformed cells which express theinserted DNA or RNA for limited periods of time.

A “transgenic organism,” as used herein, is any organism, including butnot limited to animals and plants, in which one or more of the cells ofthe organism contains heterologous nucleic acid introduced by way ofhuman intervention, such as by transgenic techniques well known in theart. The nucleic acid is introduced into the cell, directly orindirectly by introduction into a precursor of the cell, by way ofdeliberate genetic manipulation, such as by microinjection or byinfection with a recombinant virus. The term genetic manipulation doesnot include classical cross-breeding, or in vitro fertilization, butrather is directed to the introduction of a recombinant DNA molecule.The transgenic organisms contemplated in accordance with the presentinvention include bacteria, cyanobacteria, fungi, plants and animals.The isolated DNA of the present invention can be introduced into thehost by methods known in the art, for example infection, transfection,transformation or transconjugation. Techniques for transferring the DNAof the present invention into such organisms are widely known andprovided in references such as Sambrook et al. (1989), supra.

A “variant” of a particular nucleic acid sequence is defined as anucleic acid sequence having at least 40% sequence identity to theparticular nucleic acid sequence over a certain length of one of thenucleic acid sequences using blastn with the “BLAST 2 Sequences” toolVersion 2.0.9 (May 07, 1999) set at default parameters. Such a pair ofnucleic acids may show, for example, at least 50%, at least 60%, atleast 70%, at least 80%, at least 85%, at least 90%, at least 95% or atleast 98% or greater sequence identity over a certain defined length. Avariant may be described as, for example, an “allelic” (as definedabove), “splice,” “species,” or “polymorphic” variant. A splice variantmay have significant identity to a reference molecule, but willgenerally have a greater or lesser number of polynucleotides due toalternative splicing of exons during mRNA processing. The correspondingpolypeptide may possess additional functional domains or lack domainsthat are present in the reference molecule. Species variants arepolynucleotide sequences that vary from one species to another. Theresulting polypeptides will generally have significant amino acididentity relative to each other. A polymorphic variant is a variation inthe polynucleotide sequence of a particular gene between individuals ofa given species. Polymorphic variants also may encompass “singlenucleotide polymorphisms” (SNPs) in which the polynucleotide sequencevaries by one nucleotide base. The presence of SNPs may be indicativeof, for example, a certain population, a disease state, or a propensityfor a disease state.

A “variant” of a particular polypeptide sequence is defined as apolypeptide sequence having at least 40% sequence identity to theparticular polypeptide sequence over a certain length of one of thepolypeptide sequences using blastp with the “BLAST 2 Sequences” toolVersion 2.0.9 (May 07. 1999) set at default parameters. Such a pair ofpolypeptides may show, for example, at least 50%, at least 60%, at least70%, at least 80%, at least 90%, at least 95%, or at least 98% orgreater sequence identity over a certain defined length of one of thepolypeptides.

The Invention

The invention is based on the discovery of new human phosphodiesterases(HPDE), the polynucleotides encoding HPDE, and the use of thesecompositions for the diagnosis, treatment, or prevention of eye,neurological, cardiovascular, cell proliferative, andautoimmune/inflammatory disorders.

Table 1 summarizes the nomenclature for the full length polynucleotideand polypeptide sequences of the invention. Each polynucleotide and itscorresponding polypeptide are correlated to a single Incyte projectidentification number (Incyte Project ID). Each polypeptide sequence isdenoted by both a polypeptide sequence identification number(Polypeptide SEQ ID NO:) and an Incyte polypeptide sequence number(Incyte Polypeptide ID) as shown. Each polynucleotide sequence isdenoted by both a polynucleotide sequence identification number(Polynucleotide SEQ ID NO:) and an Incyte polynucleotide consensussequence number (Incyte Polynucleotide ID) as shown.

Table 2 shows sequences with homology to the polypeptides of theinvention as identified by BLAST analysis against the GenBank protein(genpept) database. Columns 1 and 2 show the polypeptide sequenceidentification number (Polypeptide SEQ ID NO:) and the correspondingIncyte polypeptide sequence number (Incyte Polypeptide ID) forpolypeptides of the invention. Column 3 shows the GenBank identificationnumber (Genbank ID NO:) of the nearest GenBank homolog. Column 4 showsthe probability score for the match between each polypeptide and itsGenBank homolog. Column 5 shows the annotation of the GenBank homolog.

Table 3 shows various structural features of the polypeptides of theinvention. Columns 1 and 2 show the polypeptide sequence identificationnumber (SEQ ID NO:) and the corresponding Incyte polypeptide sequencenumber (Incyte Polypeptide ID) for each polypeptide of the invention.Column 3 shows the number of amino acid residues in each polypeptide.Column 4 shows potential phosphorylation sites, and column 5 showspotential glycosylation sites, as determined by the MOTIFS program ofthe GCG sequence analysis software package (Genetics Computer Group,Madison Wis.). Column 6 shows amino acid residues comprising signaturesequences, domains, and motifs. Column 7 shows analytical methods forprotein structure/function analysis and in some cases, searchabledatabases to which the analytical methods were applied.

Together, Tables 2 and 3 summarize the properties of polypeptides of theinvention, and these properties establish that the claimed polypeptidesare phosphodiesterases. For example, SEQ ID NO:1 is 34% identical tohuman phosphodiesterase I/nucleotide pyrophosphatase 1 PC1/NPPS (GenBankID g9453796) as determined by the Basic Local Alignment Search Tool(BLAST). (See Table 2.) The BLAST probability score is 3.00e-63, whichindicates the probability of obtaining the observed polypeptide sequencealignment by chance. SEQ ID NO:1 also contains a type Iphosphodiesterase domain as determined by searching for statisticallysignificant matches in the hidden Markov model (HMM)-based PFAM databaseof conserved protein family domains. (See Table 3.) Data from BLASTanalyses provide further corroborative evidence that SEQ ID NO:1 is aphosphodiesterase. SEQ ID NO:2 and SEQ ID NO:3 were analyzed andannotated in a similar manner. The algorithms and parameters for theanalysis of SEQ ID NO:1-3 are described in Table 7.

As shown in Table 4, the full length polynucleotide sequences of thepresent invention were assembled using cDNA sequences or coding (exon)sequences derived from genomic DNA, or any combination of these twotypes of sequences. Columns 1 and 2 list the polynucleotide sequenceidentification number (Polynucleotide SEQ ID NO:) and the correspondingIncyte polynucleotide consensus sequence number (Incyte PolynucleotideID) for each polynucleotide of the invention. Column 3 shows the lengthof each polynucleotide sequence in basepairs. Column 4 lists fragmentsof the polynucleotide sequences which are useful, for example, inhybridization or amplification technologies that identify SEQ ID NO:4-6or that distinguish between SEQ ID NO:4-6 and related polynucleotidesequences. Column 5 shows identification numbers corresponding to cDNAsequences, coding sequences (exons) predicted from genomic DNA, and/orsequence assemblages comprised of both cDNA and genomic DNA. Thesesequences were used to assemble the full length polynucleotide sequencesof the invention. Columns 6 and 7 of Table 4 show the nucleotide start(5′) and stop (3′) positions of the cDNA sequences in column 5 relativeto their respective full length sequences.

The identification numbers in Column 5 of Table 4 may referspecifically, for example, to Incyte cDNAs along with theircorresponding cDNA libraries. For example, 6777323H1 is theidentification number of an Incyte cDNA sequence, and OVARDIR01 is thecDNA library from which it is derived. Incyte cDNAs for which cDNAlibraries are not indicated were derived from pooled cDNA libraries(e.g., 70695293V1). Alternatively, the identification numbers in column5 may refer to GenBank cDNAs or ESTs which contributed to the assemblyof the full length polynucleotide sequences. Alternatively, theidentification numbers in column 5 may refer to coding regions predictedby Genscan analysis of genomic DNA. The Genscan-predicted codingsequences may have been edited prior to assembly. (See Example IV.)Alternatively, the identification numbers in column 5 may refer toassemblages of both cDNA and Genscan-predicted exons brought together byan “exon stitching” algorithm. (See Example V.) Alternatively, theidentification numbers in column 5 may refer to assemblages of both cDNAand Genscan-predicted exons brought together by an “exon-stretching”algorithm. (See Example V.) In some cases, Incyte cDNA coverageredundant with the sequence coverage shown in column 5 was obtained toconfirm the final consensus polynucleotide sequence, but the relevantIncyte cDNA identification numbers are not shown.

Table 5 shows the representative cDNA libraries for those full lengthpolynucleotide sequences which were assembled using Incyte cDNAsequences. The representative cDNA library is the Incyte cDNA librarywhich is most frequently represented by the Incyte cDNA sequences whichwere used to assemble and confirm the above polynucleotide sequences.The tissues and vectors which were used to construct the cDNA librariesshown in Table 5 are described in Table 6.

The invention also encompasses HPDE variants. A preferred HPDE variantis one which has at least about 80%, or alternatively at least about90%, or even at least about 95% amino acid sequence identity to the HPDEamino acid sequence, and which contains at least one functional orstructural characteristic of HPDE.

The invention also encompasses polynucleotides which encode HPDE. In aparticular embodiment, the invention encompasses a polynucleotidesequence comprising a sequence selected from the group consisting of SEQID NO:4-6, which encodes HPDE. The polynucleotide sequences of SEQ IDNO:4-6, as presented in the Sequence Listing, embrace the equivalent RNAsequences, wherein occurrences of the nitrogenous base thymine arereplaced with uracil, and the sugar backbone is composed of riboseinstead of deoxyribose.

The invention also encompasses a variant of a polynucleotide sequenceencoding HPDE. In particular, such a variant polynucleotide sequencewill have at least about 70%, or alternatively at least about 85%, oreven at least about 95% polynucleotide sequence identity to thepolynucleotide sequence encoding HPDE. A particular aspect of theinvention encompasses a variant of a polynucleotide sequence comprisinga sequence selected from the group consisting of SEQ ID NO:4-6 which hasat least about 70%, or alternatively at least about 85%, or even atleast about 95% polynucleotide sequence identity to a nucleic acidsequence selected from the group consisting of SEQ ID NO:4-6. Any one ofthe polynucleotide variants described above can encode an amino acidsequence which contains at least one functional or structuralcharacteristic of HPDE.

It will be appreciated by those skilled in the art that as a result ofthe degeneracy of the genetic code, a multitude of polynucleotidesequences encoding HPDE, some bearing minimal similarity to thepolynucleotide sequences of any known and naturally occurring gene, maybe produced. Thus, the invention contemplates each and every possiblevariation of polynucleotide sequence that could be made by selectingcombinations based on possible codon choices. These combinations aremade in accordance with the standard triplet genetic code as applied tothe polynucleotide sequence of naturally occurring HPDE, and all suchvariations are to be considered as being specifically disclosed.

Although nucleotide sequences which encode HPDE and its variants aregenerally capable of hybridizing to the nucleotide sequence of thenaturally occurring HPDE under appropriately selected conditions ofstringency, it may be advantageous to produce nucleotide sequencesencoding HPDE or its derivatives possessing a substantially differentcodon usage, e.g., inclusion of non-naturally occurring codons. Codonsmay be selected to increase the rate at which expression of the peptideoccurs in a particular prokaryotic or eukaryotic host in accordance withthe frequency with which particular codons are utilized by the host.Other reasons for substantially altering the nucleotide sequenceencoding HPDE and its derivatives without altering the encoded aminoacid sequences include the production of RNA transcripts having moredesirable properties, such as a greater half-life, than transcriptsproduced from the naturally occurring sequence.

The invention also encompasses production of DNA sequences which encodeHPDE and HPDE derivatives, or fragments thereof, entirely by syntheticchemistry. After production, the synthetic sequence may be inserted intoany of the many available expression vectors and cell systems usingreagents well known in the art. Moreover, synthetic chemistry may beused to introduce mutations into a sequence encoding HPDE or anyfragment thereof.

Also encompassed by the invention are polynucleotide sequences that arecapable of hybridizing to the claimed polynucleotide sequences, and, inparticular, to those shown in SEQ ID NO:4-6 and fragments thereof undervarious conditions of stringency. (See, e.g., Wahl, G. M. and S. L.Berger (1987) Methods Enzymol. 152:399-407; Kimmel, A. R. (1987) MethodsEnzymol. 152:507-511.) Hybridization conditions, including annealing andwash conditions, are described in “Definitions.”

Methods for DNA sequencing are well known in the art and may be used topractice any of the embodiments of the invention. The methods may employsuch enzymes as the Klenow fragment of DNA polymerase I, SEQUENASE (USBiochemical, Cleveland Ohio), Taq polymerase (Applied Biosystems),thermostable T7 polymerase (Amersham Pharmacia Biotech, PiscatawayN.J.), or combinations of polymerases and proofreading exonucleases suchas those found in the ELONGASE amplification system (Life Technologies,Gaithersburg Md.). Preferably, sequence preparation is automated withmachines such as the MICROLAB 2200 liquid transfer system (Hamilton,Reno Nev.), PTC200 thermal cycler (MJ Research, Watertown Mass.) and ABICATALYST 800 thermal cycler (Applied Biosystems). Sequencing is thencarried out using either the ABI 373 or 377 DNA sequencing system(Applied Biosystems), the MEGABACE 1000 DNA sequencing system (MolecularDynamics, Sunnyvale Calif.), or other systems known in the art. Theresulting sequences are analyzed using a variety of algorithms which arewell known in the art. (See, e.g., Ausubel, F. M. (1997) Short Protocolsin Molecular Biology, John Wiley & Sons, New York N.Y., unit 7.7;Meyers, R. A. (1995) Molecular Biology and Biotechnology, Wiley VCH, NewYork N.Y., pp. 856-853.)

The nucleic acid sequences encoding HPDE may be extended utilizing apartial nucleotide sequence and employing various PCR-based methodsknown in the art to detect upstream sequences, such as promoters andregulatory elements. For example, one method which may be employed,restriction-site PCR, uses universal and nested primers to amplifyunknown sequence from genomic DNA within a cloning vector. (See, e.g.,Sarkar, G. (1993) PCR Methods Applic. 2:318-322.) Another method,inverse PCR, uses primers that extend in divergent directions to amplifyunknown sequence from a circularized template. The template is derivedfrom restriction fragments comprising a known genomic locus andsurrounding sequences. (See, e.g., Triglia, T. et al. (1988) NucleicAcids Res. 16:8186.) A third method, capture PCR, involves PCRamplification of DNA fragments adjacent to known sequences in human andyeast artificial chromosome DNA. (See, e.g., Lagerstrom, M. et al.(1991) PCR Methods Applic. 1:111-119.) In this method, multiplerestriction enzyme digestions and ligations may be used to insert anengineered double-stranded sequence into a region of unknown sequencebefore performing PCR. Other methods which may be used to retrieveunknown sequences are known in the art. (See, e.g., Parker, J. D. et al.(1991) Nucleic Acids Res. 19:3055-3060). Additionally, one may use PCR,nested primers, and PROMOTERFINDER libraries (Clontech, Palo AltoCalif.) to walk genomic DNA. This procedure avoids the need to screenlibraries and is useful in finding intron/exon junctions. For allPCR-based methods, primers may be designed using commercially availablesoftware, such as OLIGO 4.06 primer analysis software (NationalBiosciences, Plymouth Minn.) or another appropriate program, to be about22 to 30 nucleotides in length, to have a GC content of about 50% ormore, and to anneal to the template at temperatures of about 68° C. to72° C.

When screening for full length cDNAs, it is preferable to use librariesthat have been size-selected to include larger cDNAs. In addition,random-primed libraries, which often include sequences containing the 5′regions of genes, are preferable for situations in which an oligo d(T)library does not yield a full-length cDNA. Genomic libraries may beuseful for extension of sequence into 5′ non-transcribed regulatoryregions.

Capillary electrophoresis systems which are commercially available maybe used to analyze the size or confirm the nucleotide sequence ofsequencing or PCR products. In particular, capillary sequencing mayemploy flowable polymers for electrophoretic separation, four differentnucleotide-specific, laser-stimulated fluorescent dyes, and a chargecoupled device camera for detection of the emitted wavelengths.Output/light intensity may be converted to electrical signal usingappropriate software (e.g., GENOTYPER and SEQUENCE NAVIGATOR, AppliedBiosystems), and the entire process from loading of samples to computeranalysis and electronic data display may be computer controlled.Capillary electrophoresis is especially preferable for sequencing smallDNA fragments which may be present in limited amounts in a particularsample.

In another embodiment of the invention, polynucleotide sequences orfragments thereof which encode HPDE may be cloned in recombinant DNAmolecules that direct expression of HPDE, or fragments or functionalequivalents thereof, in appropriate host cells. Due to the inherentdegeneracy of the genetic code, other DNA sequences which encodesubstantially the same or a functionally equivalent amino acid sequencemay be produced and used to express HPDE.

The nucleotide sequences of the present invention can be engineeredusing methods generally known in the art in order to alter HPDE-encodingsequences for a variety of purposes including, but not limited to,modification of the cloning, processing, and/or expression of the geneproduct. DNA shuffling by random fragmentation and PCR reassembly ofgene fragments and synthetic oligonucleotides may be used to engineerthe nucleotide sequences. For example, oligonucleotide-mediatedsite-directed mutagenesis may be used to introduce mutations that createnew restriction sites, alter glycosylation patterns, change codonpreference, produce splice variants, and so forth.

The nucleotides of the present invention may be subjected to DNAshuffling techniques such as MOLECULARBREEDING (Maxygen Inc., SantaClara Calif.; described in U.S. Pat. No. 5,837,458; Chang, C.-C. et al.(1999) Nat. Biotechnol. 17:793-797; Christians, F. C. et al. (1999) Nat.Biotechnol. 17:259-264; and Crameri, A. et al. (1996) Nat. Biotechnol.14:315-319) to alter or improve the biological properties of HPDE, suchas its biological or enzymatic activity or its ability to bind to othermolecules or compounds. DNA shuffling is a process by which a library ofgene variants is produced using PCR-mediated recombination of genefragments. The library is then subjected to selection or screeningprocedures that identify those gene variants with the desiredproperties. These preferred variants may then be pooled and furthersubjected to recursive rounds of DNA shuffling and selection/screening.Thus, genetic diversity is created through “artificial” breeding andrapid molecular evolution. For example, fragments of a single genecontaining random point mutations may be recombined, screened, and thenreshuffled until the desired properties are optimized. Alternatively,fragments of a given gene may be recombined with fragments of homologousgenes in the same gene family, either from the same or differentspecies, thereby maximizing the genetic diversity of multiple naturallyoccurring genes in a directed and controllable manner.

In another embodiment, sequences encoding HPDE may be synthesized, inwhole or in part, using chemical methods well known in the art. (See,e.g., Caruthers, M. H. et al. (1980) Nucleic Acids Symp. Ser. 7:215-223;and Horn, T. et al. (1980) Nucleic Acids Symp. Ser. 7:225-232.)Alternatively, HPDE itself or a fragment thereof may be synthesizedusing chemical methods. For example, peptide synthesis can be performedusing various solution-phase or solid-phase techniques. (See, e.g.,Creighton, T. (1984) Proteins. Structures and Molecular Properties, W HFreeman, New York N.Y., pp.55-60; and Roberge, J. Y. et al. (1995)Science 269:202-204.) Automated synthesis may be achieved using the ABI431A peptide synthesizer (Applied Biosystems). Additionally, the aminoacid sequence of HPDE, or any part thereof, may be altered during directsynthesis and/or combined with sequences from other proteins, or anypart thereof, to produce a variant polypeptide or a polypeptide having asequence of a naturally occurring polypeptide.

The peptide may be substantially purified by preparative highperformance liquid chromatography. (See, e.g., Chiez, R. M. and F. Z.Regnier (1990) Methods Enzymol. 182:392-421.) The composition of thesynthetic peptides may be confirmed by amino acid analysis or bysequencing. (See, e.g., Creighton, supra, pp. 28-53.)

In order to express a biologically active HPDE, the nucleotide sequencesencoding HPDE or derivatives thereof may be inserted into an appropriateexpression vector, i.e., a vector which contains the necessary elementsfor transcriptional and translational control of the inserted codingsequence in a suitable host. These elements include regulatorysequences, such as enhancers, constitutive and inducible promoters, and5′ and 3′ untranslated regions in the vector and in polynucleotidesequences encoding HPDE. Such elements may vary in their strength andspecificity. Specific initiation signals may also be used to achievemore efficient translation of sequences encoding HPDE. Such signalsinclude the ATG initiation codon and adjacent sequences, e.g. the Kozaksequence. In cases where sequences encoding HPDE and its initiationcodon and upstream regulatory sequences are inserted into theappropriate expression vector, no additional transcriptional ortranslational control signals may be needed. However, in cases whereonly coding sequence, or a fragment thereof, is inserted, exogenoustranslational control signals including an in-frame ATG initiation codonshould be provided by the vector. Exogenous translational elements andinitiation codons may be of various origins, both natural and synthetic.The efficiency of expression may be enhanced by the inclusion ofenhancers appropriate for the particular host cell system used. (See,e.g., Scharf, D. et al. (1994) Results Probl. Cell Differ. 20:125-162.)

Methods which are well known to those skilled in the art may be used toconstruct expression vectors containing sequences encoding HPDE andappropriate transcriptional and translational control elements. Thesemethods include in vitro recombinant DNA techniques, synthetictechniques, and in vivo genetic recombination. (See, e.g., Sambrook, J.et al. (1989) Molecular Cloning, A Laboratory Manual, Cold Spring HarborPress, Plainview N.Y., ch. 4, 8, and 16-17; Ausubel, F. M. et al. (1995)Current Protocols in Molecular Biology, John Wiley & Sons, New YorkN.Y., ch. 9, 13, and 16.)

A variety of expression vector/host systems may be utilized to containand express sequences encoding HPDE. These include, but are not limitedto, microorganisms such as bacteria transformed with recombinantbacteriophage, plasmid, or cosmid DNA expression vectors; yeasttransformed with yeast expression vectors; insect cell systems infectedwith viral expression vectors (e.g., baculovirus); plant cell systemstransformed with viral expression vectors (e.g., cauliflower mosaicvirus, CaMV, or tobacco mosaic virus, TMV) or with bacterial expressionvectors (e.g., Ti or pBR322 plasmids); or animal cell systems. (See,e.g., Sambrook, supra; Ausubel, supra; Van Heeke, G. and S. M. Schuster(1989) J. Biol. Chem. 264:5503-5509; Engelhard, E. K. et al. (1994)Proc. Natl. Acad. Sci. USA 91:3224-3227; Sandig, V. et al. (1996) Hum.Gene Ther. 7:1937-1945; Takamatsu, N. (1987) EMBO J. 6:307-311; TheMcGraw Hill Yearbook of Science and Technology (1992) McGraw Hill, NewYork N.Y., pp. 191-196; Logan, J. and T. Shenk (1984) Proc. Natl. Acad.Sci. USA 81:3655-3659; and Harrington, J. J. et al. (1997) Nat. Genet.15:345-355.) Expression vectors derived from retroviruses, adenoviruses,or herpes or vaccinia viruses, or from various bacterial plasmids, maybe used for delivery of nucleotide sequences to the targeted organ,tissue, or cell population. (See, e.g., Di Nicola, M. et al. (1998)Cancer Gen. Ther. 5(6):350-356; Yu, M. et al. (1993) Proc. Natl. Acad.Sci. USA 90(13):6340-6344; Buller, R. M. et al. (1985) Nature317(6040):813-815; McGregor, D. P. et al. (1994) Mol. Immunol.31(3):219-226; and Verma, I. M. and N. Somia (1997) Nature 389:239-242.)The invention is not limited by the host cell employed.

In bacterial systems, a number of cloning and expression vectors may beselected depending upon the use intended for polynucleotide sequencesencoding HPDE. For example, routine cloning, subcloning, and propagationof polynucleotide sequences encoding HPDE can be achieved using amultifunctional E. coli vector such as PBLUESCRIPT (Stratagene, La JollaCalif.) or PSPORT1 plasmid (Life Technologies). Ligation of sequencesencoding HPDE into the vector's multiple cloning site disrupts the lacZgene, allowing a colorimetric screening procedure for identification oftransformed bacteria containing recombinant molecules. In addition,these vectors may be useful for in vitro transcription, dideoxysequencing, single strand rescue with helper phage, and creation ofnested deletions in the cloned sequence. (See, e.g., Van Heeke, G. andS. M. Schuster (1989) J. Biol. Chem. 264:5503-5509.) When largequantities of HPDE are needed, e.g. for the production of antibodies,vectors which direct high level expression of HPDE may be used. Forexample, vectors containing the strong, inducible SP6 or T7bacteriophage promoter may be used.

Yeast expression systems may be used for production of HPDE. A number ofvectors containing constitutive or inducible promoters, such as alphafactor, alcohol oxidase, and PGH promoters, may be used in the yeastSaccharomyces cerevisiae or Pichia pastoris. In addition, such vectorsdirect either the secretion or intracellular retention of expressedproteins and enable integration of foreign sequences into the hostgenome for stable propagation. (See, e.g., Ausubel, 1995, supra; Bitter,G. A. et al. (1987) Methods Enzymol. 153:516-544; and Scorer, C. A. etal. (1994) Bio/Technology 12:181-184.)

Plant systems may also be used for expression of HPDE. Transcription ofsequences encoding HPDE may be driven by viral promoters, e.g., the 35Sand 19S promoters of CaMV used alone or in combination with the omegaleader sequence from TMV (Takamatsu, N. (1987) EMBO J. 6:307-311).Alternatively, plant promoters such as the small subunit of RUBISCO orheat shock promoters may be used. (See, e.g., Coruzzi, G. et al. (1984)EMBO J. 3:1671-1680; Broglie, R. et al. (1984) Science 224:838-843; andWinter, J. et al. (1991) Results Probl. Cell Differ. 17:85-105.) Theseconstructs can be introduced into plant cells by direct DNAtransformation or pathogen-mediated transfection. (See, e.g., The McGrawHill Yearbook of Science and Technology (1992) McGraw Hill, New YorkN.Y., pp. 191-196.)

In mammalian cells, a number of viral-based expression systems may beutilized. In cases where an adenovirus is used as an expression vector,sequences encoding HPDE may be ligated into an adenovirustranscription/translation complex consisting of the late promoter andtripartite leader sequence. Insertion in a non-essential E1 or E3 regionof the viral genome may be used to obtain infective virus whichexpresses HPDE in host cells. (See, e.g., Logan, J. and T. Shenk (1984)Proc. Natl. Acad. Sci. USA 81:3655-3659.) In addition, transcriptionenhancers, such as the Rous sarcoma virus (RSV) enhancer, may be used toincrease expression in mammalian host cells. SV40 or EBV-based vectorsmay also be used for high-level protein expression.

Human artificial chromosomes (HACs) may also be employed to deliverlarger fragments of DNA than can be contained in and expressed from aplasmid. HACs of about 6 kb to 10 Mb are constructed and delivered viaconventional delivery methods (liposomes, polycationic amino polymers,or vesicles) for therapeutic purposes. (See, e.g., Harrington, J. J. etal. (1997) Nat. Genet. 15:345-355.)

For long term production of recombinant proteins in mammalian systems,stable expression of HPDE in cell lines is preferred. For example,sequences encoding HPDE can be transformed into cell lines usingexpression vectors which may contain viral origins of replication and/orendogenous expression elements and a selectable marker gene on the sameor on a separate vector. Following the introduction of the vector, cellsmay be allowed to grow for about 1 to 2 days in enriched media beforebeing switched to selective media. The purpose of the selectable markeris to confer resistance to a selective agent, and its presence allowsgrowth and recovery of cells which successfully express the introducedsequences. Resistant clones of stably transformed cells may bepropagated using tissue culture techniques appropriate to the cell type.

Any number of selection systems may be used to recover transformed celllines. These include, but are not limited to, the herpes simplex virusthymidine kinase and adenine phosphoribosyltransferase genes, for use intk⁻ and apr⁻ cells, respectively. (See, e.g., Wigler, M. et al. (1977)Cell 11:223-232; Lowy, I. et al. (1980) Cell 22:817-823.) Also,antimetabolite, antibiotic, or herbicide resistance can be used as thebasis for selection. For example, dhfr confers resistance tomethotrexate; neo confers resistance to the aminoglycosides neomycin andG-418; and als and pat confer resistance to chlorsulfuron andphosphinotricin acetyltransferase, respectively. (See, e.g., Wigler, M.et al. (1980) Proc. Natl. Acad. Sci. USA 77:3567-3570; Colbere-Garapin,F. et al. (1981) J. Mol. Biol. 150:1-14.) Additional selectable geneshave been described, e.g., trpB and hisD, which alter cellularrequirements for metabolites. (See, e.g., Hartman, S. C. and R. C.Mulligan (1988) Proc. Natl. Acad. Sci. USA 85:8047-8051.) Visiblemarkers, e.g., anthocyanins, green fluorescent proteins (GFP; Clontech),β glucuronidase and its substrate β-glucuronide, or luciferase and itssubstrate luciferin may be used. These markers can be used not only toidentify transformants, but also to quantify the amount of transient orstable protein expression attributable to a specific vector system.(See, e.g., Rhodes, C. A. (1995) Methods Mol. Biol. 55:121-131.)

Although the presence/absence of marker gene expression suggests thatthe gene of interest is also present, the presence and expression of thegene may need to be confirmed. For example, if the sequence encodingHPDE is inserted within a marker gene sequence, transformed cellscontaining sequences encoding HPDE can be identified by the absence ofmarker gene function. Alternatively, a marker gene can be placed intandem with a sequence encoding HPDE under the control of a singlepromoter. Expression of the marker gene in response to induction orselection usually indicates expression of the tandem gene as well.

In general, host cells that contain the nucleic acid sequence encodingHPDE and that express HPDE may be identified by a variety of proceduresknown to those of skill in the art. These procedures include, but arenot limited to, DNA-DNA or DNA-RNA hybridizations, PCR amplification,and protein bioassay or immunoassay techniques which include membrane,solution, or chip based technologies for the detection and/orquantification of nucleic acid or protein sequences.

Immunological methods for detecting and measuring the expression of HPDEusing either specific polyclonal or monoclonal antibodies are known inthe art. Examples of such techniques include enzyme-linked immunosorbentassays (ELISAs), radioimmunoassays (RIAs), and fluorescence activatedcell sorting (FACS). A two-site, monoclonal-based immunoassay utilizingmonoclonal antibodies reactive to two non-interfering epitopes on HPDEis preferred, but a competitive binding assay may be employed. These andother assays are well known in the art. (See, e.g., Hampton, R. et al.(1990) Serological Methods, a Laboratory Manual, APS Press, St. PaulMinn., Sect. IV; Coligan, J. E. et al. (1997) Current Protocols inImmunology, Greene Pub. Associates and Wiley-Interscience, New YorkN.Y.; and Pound, J. D. (1998) Immunochemical Protocols, Humana Press,Totowa N.J.)

A wide variety of labels and conjugation techniques are known by thoseskilled in the art and may be used in various nucleic acid and aminoacid assays. Means for producing labeled hybridization or PCR probes fordetecting sequences related to polynucleotides encoding HPDE includeoligolabeling, nick translation, end-labeling, or PCR amplificationusing a labeled nucleotide. Alternatively, the sequences encoding HPDE,or any fragments thereof, may be cloned into a vector for the productionof an mRNA probe. Such vectors are known in the art, are commerciallyavailable, and may be used to synthesize RNA probes in vitro by additionof an appropriate RNA polymerase such as T7, T3, or SP6 and labelednucleotides. These procedures may be conducted using a variety ofcommercially available kits, such as those provided by AmershamPharmacia Biotech, Promega (Madison Wis.), and US Biochemical. Suitablereporter molecules or labels which may be used for ease of detectioninclude radionuclides, enzymes, fluorescent, chemiluminescent, orchromogenic agents, as well as substrates, cofactors, inhibitors,magnetic particles, and the like.

Host cells transformed with nucleotide sequences encoding HPDE may becultured under conditions suitable for the expression and recovery ofthe protein from cell culture. The protein produced by a transformedcell may be secreted or retained intracellularly depending on thesequence and/or the vector used. As will be understood by those of skillin the art, expression vectors containing polynucleotides which encodeHPDE may be designed to contain signal sequences which direct secretionof HPDE through a prokaryotic or eukaryotic cell membrane.

In addition, a host cell strain may be chosen for its ability tomodulate expression of the inserted sequences or to process theexpressed protein in the desired fashion. Such modifications of thepolypeptide include, but are not limited to, acetylation, carboxylation,glycosylation, phosphorylation, lipidation, and acylation.Post-translational processing which cleaves a “prepro” or “pro” form ofthe protein may also be used to specify protein targeting, folding,and/or activity. Different host cells which have specific cellularmachinery and characteristic mechanisms for post-translationalactivities (e.g., CHO, HeLa, MDCK, HEK293, and WI38) are available fromthe American Type Culture Collection (ATCC, Manassas Va.) and may bechosen to ensure the correct modification and processing of the foreignprotein.

In another embodiment of the invention, natural, modified, orrecombinant nucleic acid sequences encoding HPDE may be ligated to aheterologous sequence resulting in translation of a fusion protein inany of the aforementioned host systems. For example, a chimeric HPDEprotein containing a heterologous moiety that can be recognized by acommercially available antibody may facilitate the screening of peptidelibraries for inhibitors of HPDE activity. Heterologous protein andpeptide moieties may also facilitate purification of fusion proteinsusing commercially available affinity matrices. Such moieties include,but are not limited to, glutathione S-transferase (GST), maltose bindingprotein (MBP), thioredoxin (Trx), calmodulin binding peptide (CBP),6-His, FLAG, c-myc, and hemagglutinin (HA). GST, MBP, Trx, CBP, and6-His enable purification of their cognate fusion proteins onimmobilized glutathione, maltose, phenylarsine oxide, calmodulin, andmetal-chelate resins, respectively. FLAG, c-myc, and hemagglutinin (HA)enable immunoaffinity purification of fusion proteins using commerciallyavailable monoclonal and polyclonal antibodies that specificallyrecognize these epitope tags. A fusion protein may also be engineered tocontain a proteolytic cleavage site located between the HPDE encodingsequence and the heterologous protein sequence, so that HPDE may becleaved away from the heterologous moiety following purification.Methods for fusion protein expression and purification are discussed inAusubel (1995, supra, ch. 10). A variety of commercially available kitsmay also be used to facilitate expression and purification of fusionproteins.

In a further embodiment of the invention, synthesis of radiolabeled HPDEmay be achieved in vitro using the TNT rabbit reticulocyte lysate orwheat germ extract system (Promega). These systems couple transcriptionand translation of protein-coding sequences operably associated with theT7, T3, or SP6 promoters. Translation takes place in the presence of aradiolabeled amino acid precursor, for example, ³⁵S-methionine.

HPDE of the present invention or fragments thereof may be used to screenfor compounds that specifically bind to HPDE. At least one and up to aplurality of test compounds may be screened for specific binding toHPDE. Examples of test compounds include antibodies, oligonucleotides,proteins (e.g., receptors), or small molecules.

In one embodiment, the compound thus identified is closely related tothe natural ligand of HPDE, e.g., a ligand or fragment thereof, anatural substrate, a structural or functional mimetic, or a naturalbinding partner. (See, e.g., Coligan, J. E. et al. (1991) CurrentProtocols in Immunology 1(2): Chapter 5.) Similarly, the compound can beclosely related to the natural receptor to which HPDE binds, or to atleast a fragment of the receptor, e.g., the ligand binding site. Ineither case, the compound can be rationally designed using knowntechniques. In one embodiment, screening for these compounds involvesproducing appropriate cells which express HPDE, either as a secretedprotein or on the cell membrane. Preferred cells include cells frommammals, yeast, Drosophila, or E. coli. Cells expressing HPDE or cellmembrane fractions which contain HPDE are then contacted with a testcompound and binding, stimulation, or inhibition of activity of eitherHPDE or the compound is analyzed.

An assay may simply test binding of a test compound to the polypeptide,wherein binding is detected by a fluorophore, radioisotope, enzymeconjugate, or other detectable label. For example, the assay maycomprise the steps of combining at least one test compound with HPDE,either in solution or affixed to a solid support, and detecting thebinding of HPDE to the compound. Alternatively, the assay may detect ormeasure binding of a test compound in the presence of a labeledcompetitor. Additionally, the assay may be carried out using cell-freepreparations, chemical libraries, or natural product mixtures, and thetest compound(s) may be free in solution or affixed to a solid support.

HPDE of the present invention or fragments thereof may be used to screenfor compounds that modulate the activity of HPDE. Such compounds mayinclude agonists, antagonists, or partial or inverse agonists. In oneembodiment, an assay is performed under conditions permissive for HPDEactivity, wherein HPDE is combined with at least one test compound, andthe activity of HPDE in the presence of a test compound is compared withthe activity of HPDE in the absence of the test compound. A change inthe activity of HPDE in the presence of the test compound is indicativeof a compound that modulates the activity of HPDE. Alternatively, a testcompound is combined with an in vitro or cell-free system comprisingHPDE under conditions suitable for HPDE activity, and the assay isperformed. In either of these assays, a test compound which modulatesthe activity of HPDE may do so indirectly and need not come in directcontact with the test compound. At least one and up to a plurality oftest compounds may be screened.

In another embodiment, polynucleotides encoding HPDE or their mammalianhomologs may be “knocked out” in an animal model system using homologousrecombination in embryonic stem (ES) cells. Such techniques are wellknown in the art and are useful for the generation of animal models ofhuman disease. (See, e.g., U.S. Pat. Nos. 5,175,383 and 5,767,337.) Forexample, mouse ES cells, such as the mouse 129/SvJ cell line, arederived from the early mouse embryo and grown in culture. The ES cellsare transformed with a vector containing the gene of interest disruptedby a marker gene, e.g., the neomycin phosphotransferase gene (neo;Capecchi, M. R. (1989) Science 244:1288-1292). The vector integratesinto the corresponding region of the host genome by homologousrecombination. Alternatively, homologous recombination takes place usingthe Cre-loxP system to knockout a gene of interest in a tissue- ordevelopmental stage-specific manner (Marth, J. D. (1996) Clin. Invest.97:1999-2002; Wagner, K. U. et al. (1997) Nucleic Acids Res.25:4323-4330). Transformed ES cells are identified and microinjectedinto mouse cell blastocysts such as those from the C57BL/6 mouse strain.The blastocysts are surgically transferred to pseudopregnant dams, andthe resulting chimeric progeny are genotyped and bred to produceheterozygous or homozygous strains. Transgenic animals thus generatedmay be tested with potential therapeutic or toxic agents.

Polynucleotides encoding HPDE may also be manipulated in vitro in EScells derived from human blastocysts. Human ES cells have the potentialto differentiate into at least eight separate cell lineages includingendoderm, mesoderm, and ectodermal cell types. These cell lineagesdifferentiate into, for example, neural cells, hematopoietic lineages,and cardiomyocytes (Thomson, J. A. et al. (1998) Science 282:1145-1147).

Polynucleotides encoding HPDE can also be used to create “knockin”humanized animals (pigs) or transgenic animals (mice or rats) to modelhuman disease. With knockin technology, a region of a polynucleotideencoding HPDE is injected into animal ES cells, and the injectedsequence integrates into the animal cell genome. Transformed cells areinjected into blastulae, and the blastulae are implanted as describedabove. Transgenic progeny or inbred lines are studied and treated withpotential pharmaceutical agents to obtain information on treatment of ahuman disease. Alternatively, a mammal inbred to overexpress HPDE, e.g.,by secreting HPDE in its milk, may also serve as a convenient source ofthat protein (Janne, J. et al. (1998) Biotechnol. Annu. Rev. 4:55-74).

Therapeutics

Chemical and structural similarity, e.g., in the context of sequencesand motifs, exists between regions of HPDE and phosphodiesterases.Therefore, HPDE appears to play a role in eye, neurological,cardiovascular, cell proliferative, and autoimmune/inflammatorydisorders. In the treatment of disorders associated with increased HPDEexpression or activity, it is desirable to decrease the expression oractivity of HPDE. In the treatment of disorders associated withdecreased HPDE expression or activity, it is desirable to increase theexpression or activity of HPDE.

Therefore, in one embodiment, HPDE or a fragment or derivative thereofmay be administered to a subject to treat or prevent a disorderassociated with decreased expression or activity of HPDE. Examples ofsuch disorders include, but are not limited to, an eye disorder, such asconjunctivitis, keratoconjunctivitis sicca, keratitis, episcleritis,iritis, posterior uveitis, glaucoma, amaurosis fugax, ischemic opticneuropathy, optic neuritis, Leber's hereditary optic neuropathy, toxicoptic neuropathy, vitreous detachment, retinal detachment, cataract,macular degeneration, central serous chorioretinopathy, retinitispigmentosa, melanoma of the choroid, retrobulbar tumor, and chiasmaltumor; a neurological disorder, such as epilepsy, ischemiccerebrovascular disease, stroke, cerebral neoplasms, Alzheimer'sdisease, Pick's disease, Huntington's disease, dementia, Parkinson'sdisease and other extrapyramidal disorders, amyotrophic lateralsclerosis and other motor neuron disorders, progressive neural muscularatrophy, retinitis pigmentosa, hereditary ataxias, multiple sclerosisand other demyelinating diseases, bacterial and viral meningitis, brainabscess, subdural empyema, epidural abscess, suppurative intracranialthrombophlebitis, myelitis and radiculitis, viral central nervous systemdisease, prion diseases including kuru, Creutzfeldt-Jakob disease, andGerstmann-Straussler-Scheinker syndrome, fatal familial insomnia,nutritional and metabolic diseases of the nervous system,neurofibromatosis, tuberous sclerosis, cerebelloretinalhemangioblastomatosis, encephalotrigeminal syndrome, mental retardationand other developmental disorders of the central nervous systemincluding Down syndrome, cerebral palsy, neuroskeletal disorders,autonomic nervous system disorders, cranial nerve disorders, spinal corddiseases, muscular dystrophy and other neuromuscular disorders,peripheral nervous system disorders, dermatomyositis and polymyositis,inherited, metabolic, endocrine, and toxic myopathies, myastheniagravis, periodic paralysis, mental disorders including mood, anxiety,and schizophrenic disorders, seasonal affective disorder (SAD),akathesia, amnesia, catatonia, diabetic neuropathy, tardive dyskinesia,dystonias, paranoid psychoses, postherpetic neuralgia, Tourette'sdisorder, progressive supranuclear palsy, corticobasal degeneration, andfamilial frontotemporal dementia; a cardiovascular disorder, such asarterioyenous fistula, atherosclerosis, hypertension, vasculitis,Raynaud's disease, aneurysms, arterial dissections, varicose veins,thrombophlebitis and phlebothrombosis, vascular tumors, andcomplications of thrombolysis, balloon angioplasty, vascularreplacement, and coronary artery bypass graft surgery, congestive heartfailure, ischemic heart disease, angina pectoris, myocardial infarction,hypertensive heart disease, degenerative valvular heart disease,calcific aortic valve stenosis, congenitally bicuspid aortic valve,mitral annular calcification, mitral valve prolapse, rheumatic fever andrheumatic heart disease, infective endocarditis, nonbacterial thromboticendocarditis, endocarditis of systemic lupus erythematosus, carcinoidheart disease, cardiomyopathy, myocarditis, pericarditis, neoplasticheart disease, congenital heart disease, and complications of cardiactransplantation, congenital lung anomalies, atelectasis, pulmonarycongestion and edema, pulmonary embolism, pulmonary hemorrhage,pulmonary infarction, pulmonary hypertension, vascular sclerosis,obstructive pulmonary disease, restrictive pulmonary disease, chronicobstructive pulmonary disease, emphysema, chronic bronchitis, bronchialasthma, bronchiectasis, bacterial pneumonia, viral and mycoplasmalpneumonia, lung abscess, pulmonary tuberculosis, diffuse interstitialdiseases, pneumoconioses, sarcoidosis, idiopathic pulmonary fibrosis,desquamative interstitial pneumonitis, hypersensitivity pneumonitis,pulmonary eosinophilia bronchiolitis obliterans-organizing pneumonia,diffuse pulmonary hemorrhage syndromes, Goodpasture's syndromes,idiopathic pulmonary hemosiderosis, pulmonary involvement incollagen-vascular disorders, pulmonary alveolar proteinosis, lungtumors, inflammatory and noninflammatory pleural effusions,pneumothorax, pleural tumors, drug-induced lung disease,radiation-induced lung disease, and complications of lungtransplantation; a cell proliferative disorder, such as actinickeratosis, arteriosclerosis, atherosclerosis, bursitis, cirrhosis,hepatitis, mixed connective tissue disease (MCTD), myelofibrosis,paroxysmal nocturnal hemoglobinuria, polycythemia vera, psoriasis,primary thrombocythemia, and cancers including adenocarcinoma, leukemia,lymphoma, melanoma, myeloma, sarcoma, teratocarcinoma, and, inparticular, cancers of the adrenal gland, bladder, bone, bone marrow,brain, breast, cervix, gall bladder, ganglia, gastrointestinal tract,heart, kidney, liver, lung, muscle, ovary, pancreas, parathyroid, penis,prostate, salivary glands, skin, spleen, testis, thymus, thyroid, anduterus; and an autoimmune/inflammatory disorder, acquiredimmunodeficiency syndrome (AIDS), Addison's disease, adult respiratorydistress syndrome, allergies, ankylosing spondylitis, amyloidosis,anemia, asthma, atherosclerosis, autoimmune hemolytic anemia, autoimmunethyroiditis, autoimmune polyendocrinopathy-candidiasis-ectodermaldystrophy (APECED), bronchitis, cholecystitis, contact dermatitis,Crohn's disease, atopic dermatitis, dermatomyositis, diabetes mellitus,emphysema, episodic lymphopenia with lymphocytotoxins, erythroblastosisfetalis, erythema nodosum, atrophic gastritis, glomerulonephritis,Goodpasture's syndrome, gout, Graves' disease, Hashimoto's thyroiditis,hypereosinophilia, irritable bowel syndrome, multiple sclerosis,myasthenia gravis, myocardial or pericardial inflammation,osteoarthritis, osteoporosis, pancreatitis, polymyositis, psoriasis,Reiter's syndrome, rheumatoid arthritis, scleroderma, Sjögren'ssyndrome, systemic anaphylaxis, systemic lupus erythematosus, systemicsclerosis, thrombocytopenic purpura, ulcerative colitis, uveitis, Wernersyndrome, complications of cancer, hemodialysis, and extracorporealcirculation, viral, bacterial, fungal, parasitic, protozoal, andhelminthic infections, and trauma.

In another embodiment, a vector capable of expressing HPDE or a fragmentor derivative thereof may be administered to a subject to treat orprevent a disorder associated with decreased expression or activity ofHPDE including, but not limited to, those described above.

In a further embodiment, a composition comprising a substantiallypurified HPDE in conjunction with a suitable pharmaceutical carrier maybe administered to a subject to treat or prevent a disorder associatedwith decreased expression or activity of HPDE including, but not limitedto, those provided above.

In still another embodiment, an agonist which modulates the activity ofHPDE may be administered to a subject to treat or prevent a disorderassociated with decreased expression or activity of HPDE including, butnot limited to, those listed above.

In a further embodiment, an antagonist of HPDE may be administered to asubject to treat or prevent a disorder associated with increasedexpression or activity of HPDE. Examples of such disorders include, butare not limited to, those eye, neurological, cardiovascular, cellproliferative, and autoimmune/inflammatory disorders described above. Inone aspect, an antibody which specifically binds HPDE may be useddirectly as an antagonist or indirectly as a targeting or deliverymechanism for bringing a pharmaceutical agent to cells or tissues whichexpress HPDE.

In an additional embodiment, a vector expressing the complement of thepolynucleotide encoding HPDE may be administered to a subject to treator prevent a disorder associated with increased expression or activityof HPDE including, but not limited to, those described above.

In other embodiments, any of the proteins, antagonists, antibodies,agonists, complementary sequences, or vectors of the invention may beadministered in combination with other appropriate therapeutic agents.Selection of the appropriate agents for use in combination therapy maybe made by one of ordinary skill in the art, according to conventionalpharmaceutical principles. The combination of therapeutic agents may actsynergistically to effect the treatment or prevention of the variousdisorders described above. Using this approach, one may be able toachieve therapeutic efficacy with lower dosages of each agent, thusreducing the potential for adverse side effects.

An antagonist of HPDE may be produced using methods which are generallyknown in the art. In particular, purified HPDE may be used to produceantibodies or to screen libraries of pharmaceutical agents to identifythose which specifically bind HPDE. Antibodies to HPDE may also begenerated using methods that are well known in the art. Such antibodiesmay include, but are not limited to, polyclonal, monoclonal, chimeric,and single chain antibodies, Fab fragments, and fragments produced by aFab expression library. Neutralizing antibodies (i.e., those whichinhibit dimer formation) are generally preferred for therapeutic use.

For the production of antibodies, various hosts including goats,rabbits, rats, mice, humans, and others may be immunized by injectionwith HPDE or with any fragment or oligopeptide thereof which hasimmunogenic properties. Depending on the host species, various adjuvantsmay be used to increase immunological response. Such adjuvants include,but are not limited to, Freund's, mineral gels such as aluminumhydroxide, and surface active substances such as lysolecithin, pluronicpolyols, polyanions, peptides, oil emulsions, KLH, and dinitrophenol.Among adjuvants used in humans, BCG (bacilli Calmette-Guerin) andCorynebacterium parvum are especially preferable.

It is preferred that the oligopeptides, peptides, or fragments used toinduce antibodies to HPDE have an amino acid sequence consisting of atleast about 5 amino acids, and generally will consist of at least about10 amino acids. It is also preferable that these oligopeptides,peptides, or fragments are identical to a portion of the amino acidsequence of the natural protein. Short stretches of HPDE amino acids maybe fused with those of another protein, such as KLH, and antibodies tothe chimeric molecule may be produced.

Monoclonal antibodies to HPDE may be prepared using any technique whichprovides for the production of antibody molecules by continuous celllines in culture. These include, but are not limited to, the hybridomatechnique, the human B-cell hybridoma technique, and the EBV-hybridomatechnique. (See, e.g., Kohler, G. et al. (1975) Nature 256:495-497;Kozbor, D. et al. (1985) J. Immunol. Methods 81:31-42; Cote, R. J. etal. (1983) Proc. Natl. Acad. Sci. USA 80:2026-2030; and Cole, S. P. etal. (1984) Mol. Cell Biol. 62:109-120.)

In addition, techniques developed for the production of “chimericantibodies,” such as the splicing of mouse antibody genes to humanantibody genes to obtain a molecule with appropriate antigen specificityand biological activity, can be used. (See, e.g., Morrison, S. L. et al.(1984) Proc. Natl. Acad. Sci. USA 81:6851-6855; Neuberger, M. S. et al.(1984) Nature 312:604-608; and Takeda, S. et al. (1985) Nature314:452-454.) Alternatively, techniques described for the production ofsingle chain antibodies may be adapted, using methods known in the art,to produce HPDE-specific single chain antibodies. Antibodies withrelated specificity, but of distinct idiotypic composition, may begenerated by chain shuffling from random combinatorial immunoglobulinlibraries. (See, e.g., Burton, D. R. (1991) Proc. Natl. Acad. Sci. USA88:10134-10137.)

Antibodies may also be produced by inducing in vivo production in thelymphocyte population or by screening immunoglobulin libraries or panelsof highly specific binding reagents as disclosed in the literature.(See, e.g., Orlandi, R. et al. (1989) Proc. Natl. Acad. Sci. USA86:3833-3837; Winter, G. et al. (1991) Nature 349:293-299.)

Antibody fragments which contain specific binding sites for HPDE mayalso be generated. For example, such fragments include, but are notlimited to, F(ab′)₂ fragments produced by pepsin digestion of theantibody molecule and Fab fragments generated by reducing the disulfidebridges of the F(ab′)₂ fragments. Alternatively, Fab expressionlibraries may be constructed to allow rapid and easy identification ofmonoclonal Fab fragments with the desired specificity. (See, e.g., Huse,W. D. et al. (1989) Science 246:1275-1281.)

Various immunoassays may be used for screening to identify antibodieshaving the desired specificity. Numerous protocols for competitivebinding or immunoradiometric assays using either polyclonal ormonoclonal antibodies with established specificities are well known inthe art. Such immunoassays typically involve the measurement of complexformation between HPDE and its specific antibody. A two-site,monoclonal-based immunoassay utilizing monoclonal antibodies reactive totwo non-interfering HPDE epitopes is generally used, but a competitivebinding assay may also be employed (Pound, supra).

Various methods such as Scatchard analysis in conjunction withradioimmunoassay techniques may be used to assess the affinity ofantibodies for HPDE. Affinity is expressed as an association constant,K_(a), which is defined as the molar concentration of HPDE-antibodycomplex divided by the molar concentrations of free antigen and freeantibody under equilibrium conditions. The K_(a) determined for apreparation of polyclonal antibodies, which are heterogeneous in theiraffinities for multiple HPDE epitopes, represents the average affinity,or avidity, of the antibodies for HPDE. The K_(a) determined for apreparation of monoclonal antibodies, which are monospecific for aparticular HPDE epitope, represents a true measure of affinity.High-affinity antibody preparations with K_(a) ranging from about 10⁹ to10¹² L/mole are preferred for use in immunoassays in which theHPDE-antibody complex must withstand rigorous manipulations.Low-affinity antibody preparations with K_(a) ranging from about 10⁶ to10⁷ L/mole are preferred for use in immunopurification and similarprocedures which ultimately require dissociation of HPDE, preferably inactive form, from the antibody (Catty, D. (1988) Antibodies, Volume I: APractical Approach, IRL Press, Washington D.C.; Liddell, J. E. and A.Cryer (1991) A Practical Guide to Monoclonal Antibodies, John Wiley &Sons, New York N.Y.).

The titer and avidity of polyclonal antibody preparations may be furtherevaluated to determine the quality and suitability of such preparationsfor certain downstream applications. For example, a polyclonal antibodypreparation containing at least 1-2 mg specific antibody/ml, preferably5-10 mg specific antibody/ml, is generally employed in proceduresrequiring precipitation of HPDE-antibody complexes. Procedures forevaluating antibody specificity, titer, and avidity, and guidelines forantibody quality and usage in various applications, are generallyavailable. (See, e.g., Catty, supra, and Coligan et al. supra.)

In another embodiment of the invention, the polynucleotides encodingHPDE, or any fragment or complement thereof, may be used for therapeuticpurposes. In one aspect, modifications of gene expression can beachieved by designing complementary sequences or antisense molecules(DNA, RNA, PNA, or modified oligonucleotides) to the coding orregulatory regions of the gene encoding HPDE. Such technology is wellknown in the art, and antisense oligonucleotides or larger fragments canbe designed from various locations along the coding or control regionsof sequences encoding HPDE. (See, e.g., Agrawal, S., ed. (1996)Antisense Therapeutics, Humana Press Inc., Totawa N.J.)

In therapeutic use, any gene delivery system suitable for introductionof the antisense sequences into appropriate target cells can be used.Antisense sequences can be delivered intracellularly in the form of anexpression plasmid which, upon transcription, produces a sequencecomplementary to at least a portion of the cellular sequence encodingthe target protein. (See, e.g., Slater, J. E. et al. (1998) J. AllergyCli. Immunol. 102(3):469-475; and Scanlon, K. J. et al. (1995)9(13):1288-1296.) Antisense sequences can also be introducedintracellularly through the use of viral vectors, such as retrovirus andadeno-associated virus vectors. (See, e.g., Miller, A. D. (1990) Blood76:271; Ausubel, supra; Uckert, W. and W. Walther (1994) Pharmacol.Ther. 63(3):323-347.) Other gene delivery mechanisms includeliposome-derived systems, artificial viral envelopes, and other systemsknown in the art. (See, e.g., Rossi, J. J. (1995) Br. Med. Bull.51(1):217-225; Boado, R. J. et al. (1998) J. Pharm. Sci.87(11):1308-1315; and Morris, M. C. et al. (1997) Nucleic Acids Res.25(14):2730-2736.)

In another embodiment of the invention, polynucleotides encoding HPDEmay be used for somatic or germline gene therapy. Gene therapy may beperformed to (i) correct a genetic deficiency (e.g., in the cases ofsevere combined immunodeficiency (SCID)-X1 disease characterized byX-linked inheritance (Cavazzana-Calvo, M. et al. (2000) Science288:669-672), severe combined immunodeficiency syndrome associated withan inherited adenosine deaminase (ADA) deficiency (Blaese, R. M. et al.(1995) Science 270:475-480; Bordignon, C. et al. (1995) Science270:470-475), cystic fibrosis (Zabner, J. et al. (1993) Cell 75:207-216;Crystal, R. G. et al. (1995) Hum. Gene Therapy 6:643-666; Crystal, R. G.et al. (1995) Hum. Gene Therapy 6:667-703), thalassamias, familialhypercholesterolemia, and hemophilia resulting from Factor VIII orFactor IX deficiencies (Crystal, R. G. (1995) Science 270:404-410;Verma, I. M. and N. Somia (1997) Nature 389:239-242)), (ii) express aconditionally lethal gene product (e.g., in the case of cancers whichresult from unregulated cell proliferation), or (iii) express a proteinwhich affords protection against intracellular parasites (e.g., againsthuman retroviruses, such as human immunodeficiency virus (HIV)(Baltimore, D. (1988) Nature 335:395-396; Poeschla, E. et al. (1996)Proc. Natl. Acad. Sci. USA. 93:11395-11399), hepatitis B or C virus(HBV, HCV); fungal parasites, such as Candida albicans andParacoccidioides brasiliensis; and protozoan parasites such asPlasmodium falciparum and Trypanosoma cruzi). In the case where agenetic deficiency in HPDE expression or regulation causes disease, theexpression of HPDE from an appropriate population of transduced cellsmay alleviate the clinical manifestations caused by the geneticdeficiency.

In a further embodiment of the invention, diseases or disorders causedby deficiencies in HPDE are treated by constructing mammalian expressionvectors encoding HPDE and introducing these vectors by mechanical meansinto HPDE-deficient cells. Mechanical transfer technologies for use withcells in vivo or ex vitro include (i) direct DNA microinjection intoindividual cells, (ii) ballistic gold particle delivery, (iii)liposome-mediated transfection, (iv) receptor-mediated gene transfer,and (v) the use of DNA transposons (Morgan, R. A. and W. F. Anderson(1993) Annu. Rev. Biochem. 62:191-217; Ivics, Z. (1997) Cell 91:501-510;Boulay, J-L. and H. Récipon (1998) Curr. Opin. Biotechnol. 9:445-450).

Expression vectors that may be effective for the expression of HPDEinclude, but are not limited to, the PCDNA 3.1, EPITAG, PRCCMV2, PREP,PVAX vectors (Invitrogen, Carlsbad Calif.), PCMV-SCRIPT, PCMV-TAG,PEGSH/PERV (Stratagene, La Jolla Calif.), and PTET-OFF, PTET-ON, PTRE2,PTRE2-LUC, PTK-HYG (Clontech, Palo Alto Calif.). HPDE may be expressedusing (i) a constitutively active promoter, (e.g., from cytomegalovirus(CMV), Rous sarcoma virus (RSV), SV40 virus, thymidine kinase (TK), orβ-actin genes), (ii) an inducible promoter (e.g., thetetracycline-regulated promoter (Gossen, M. and H. Bujard (1992) Proc.Natl. Acad. Sci. USA 89:5547-5551; Gossen, M. et al. (1995) Science268:1766-1769; Rossi, F. M. V. and H. M. Blau (1998) Curr. Opin.Biotechnol. 9:451-456), commercially available in the T-REX plasmid(Invitrogen)); the ecdysone-inducible promoter (available in theplasmids PVGRXR and PIND; Invitrogen); the FK506/rapamycin induciblepromoter; or the RU486/mifepristone inducible promoter (Rossi, F. M. V.and Blau, H. M. supra)), or (iii) a tissue-specific promoter or thenative promoter of the endogenous gene encoding HPDE from a normalindividual.

Commercially available liposome transformation kits (e.g., the PERFECTLIPID TRANSFECTION KIT, available from Invitrogen) allow one withordinary skill in the art to deliver polynucleotides to target cells inculture and require minimal effort to optimize experimental parameters.In the alternative, transformation is performed using the calciumphosphate method (Graham, F. L. and A. J. Eb (1973) Virology52:456-467), or by electroporation (Neumann, E. et al. (1982) EMBO J.1:841-845). The introduction of DNA to primary cells requiresmodification of these standardized mammalian transfection protocols.

In another embodiment of the invention, diseases or disorders caused bygenetic defects with respect to HPDE expression are treated byconstructing a retrovirus vector consisting of (i) the polynucleotideencoding HPDE under the control of an independent promoter or theretrovirus long terminal repeat (LTR) promoter, (ii) appropriate RNApackaging signals, and (iii) a Rev-responsive element (RRE) along withadditional retrovirus cis-acting RNA sequences and coding sequencesrequired for efficient vector propagation. Retrovirus vectors (e.g., PFBand PFBNEO) are commercially available (Stratagene) and are based onpublished data (Riviere, I. et al. (1995) Proc. Natl. Acad. Sci. USA92:6733-6737), incorporated by reference herein. The vector ispropagated in an appropriate vector producing cell line (VPCL) thatexpresses an envelope gene with a tropism for receptors on the targetcells or a promiscuous envelope protein such as VSVg (Armentano, D. etal. (1987) J. Virol. 61:1647-1650; Bender, M. A. et al. (1987) J. Virol.61:1639-1646; Adam, M. A. and A. D. Miller (1988) J. Virol.62:3802-3806; Dull, T. et al. (1998) J. Virol. 72:8463-8471; Zufferey,R. et al. (1998) J. Virol. 72:9873-9880). U.S. Pat. No. 5,910,434 toRigg (“Method for obtaining retrovirus packaging cell lines producinghigh transducing efficiency retroviral supernatant”) discloses a methodfor obtaining retrovirus packaging cell lines and is hereby incorporatedby reference. Propagation of retrovirus vectors, transduction of apopulation of cells (e.g., CD4⁺ T-cells), and the return of transducedcells to a patient are procedures well known to persons skilled in theart of gene therapy and have been well documented (Ranga, U. et al.(1997) J. Virol. 71:7020-7029; Bauer, G. et al. (1997) Blood89:2259-2267; Bonyhadi, M. L. (1997) J. Virol. 71:4707-4716; Ranga, U.et al. (1998) Proc. Natl. Acad. Sci. USA 95:1201-1206; Su, L. (1997)Blood 89:2283-2290).

In the alternative, an adenovirus-based gene therapy delivery system isused to deliver polynucleotides encoding HPDE to cells which have one ormore genetic abnormalities with respect to the expression of HPDE. Theconstruction and packaging of adenovirus-based vectors are well known tothose with ordinary skill in the art. Replication defective adenovirusvectors have proven to be versatile for importing genes encodingimmunoregulatory proteins into intact islets in the pancreas (Csete, M.E. et al. (1995) Transplantation 27:263-268). Potentially usefuladenoviral vectors are described in U.S. Pat. No. 5,707,618 to Armentano(“Adenovirus vectors for gene therapy”), hereby incorporated byreference. For adenoviral vectors, see also Antinozzi, P. A. et al.(1999) Annu. Rev. Nutr. 19:511-544 and Verma, I. M. and N. Somia (1997)Nature 18:389:239-242, both incorporated by reference herein.

In another alternative, a herpes-based, gene therapy delivery system isused to deliver polynucleotides encoding HPDE to target cells which haveone or more genetic abnormalities with respect to the expression ofHPDE. The use of herpes simplex virus (HSV)-based vectors may beespecially valuable for introducing HPDE to cells of the central nervoussystem, for which HSV has a tropism. The construction and packaging ofherpes-based vectors are well known to those with ordinary skill in theart. A replication-competent herpes simplex virus (HSV) type 1-basedvector has been used to deliver a reporter gene to the eyes of primates(Liu, X. et al. (1999) Exp. Eye Res. 169:385-395). The construction of aHSV-1 virus vector has also been disclosed in detail in U.S. Pat. No.5,804,413 to DeLuca (“Herpes simplex virus strains for gene transfer”),which is hereby incorporated by reference. U.S. Pat. No. 5,804,413teaches the use of recombinant HSV d92 which consists of a genomecontaining at least one exogenous gene to be transferred to a cell underthe control of the appropriate promoter for purposes including humangene therapy. Also taught by this patent are the construction and use ofrecombinant HSV strains deleted for ICP4, ICP27 and ICP22. For HSVvectors, see also Goins, W. F. et al. (1999) J. Virol. 73:519-532 andXu, H. et al. (1994) Dev. Biol. 163:152-161, hereby incorporated byreference. The manipulation of cloned herpesvirus sequences, thegeneration of recombinant virus following the transfection of multipleplasmids containing different segments of the large herpesvirus genomes,the growth and propagation of herpesvirus, and the infection of cellswith herpesvirus are techniques well known to those of ordinary skill inthe art.

In another alternative, an alphavirus (positive, single-stranded RNAvirus) vector is used to deliver polynucleotides encoding HPDE to targetcells. The biology of the prototypic alphavirus, Semliki Forest Virus(SFV), has been studied extensively and gene transfer vectors have beenbased on the SFV genome (Garoff, H. and K.-J. Li (1998) Curr. Opin.Biotechnol. 9:464-469). During alphavirus RNA replication, a subgenomicRNA is generated that normally encodes the viral capsid proteins. Thissubgenomic RNA replicates to higher levels than the full length genomicRNA, resulting in the overproduction of capsid proteins relative to theviral proteins with enzymatic activity (e.g., protease and polymerase).Similarly, inserting the coding sequence for HPDE into the alphavirusgenome in place of the capsid-coding region results in the production ofa large number of HPDE-coding RNAs and the synthesis of high levels ofHPDE in vector transduced cells. While alphavirus infection is typicallyassociated with cell lysis within a few days, the ability to establish apersistent infection in hamster normal kidney cells (BHK-21) with avariant of Sindbis virus (SIN) indicates that the lytic replication ofalphaviruses can be altered to suit the needs of the gene therapyapplication (Dryga, S. A. et al. (1997) Virology 228:74-83). The widehost range of alphaviruses will allow the introduction of HPDE into avariety of cell types. The specific transduction of a subset of cells ina population may require the sorting of cells prior to transduction. Themethods of manipulating infectious cDNA clones of alphaviruses,performing alphavirus cDNA and RNA transfections, and performingalphavirus infections, are well known to those with ordinary skill inthe art.

Oligonucleotides derived from the transcription initiation site, e.g.,between about positions −10 and +10 from the start site, may also beemployed to inhibit gene expression. Similarly, inhibition can beachieved using triple helix base-pairing methodology. Triple helixpairing is useful because it causes inhibition of the ability of thedouble helix to open sufficiently for the binding of polymerases,transcription factors, or regulatory molecules. Recent therapeuticadvances using triplex DNA have been described in the literature. (See,e.g., Gee, J. E. et al. (1994) in Huber, B. E. and B. I. Carr, Molecularand Immunologic Approaches, Futura Publishing, Mt. Kisco N.Y., pp.163-177.) A complementary sequence or antisense molecule may also bedesigned to block translation of mRNA by preventing the transcript frombinding to ribosomes.

Ribozymes, enzymatic RNA molecules, may also be used to catalyze thespecific cleavage of RNA. The mechanism of ribozyme action involvessequence-specific hybridization of the ribozyme molecule tocomplementary target RNA, followed by endonucleolytic cleavage. Forexample, engineered hammerhead motif ribozyme molecules may specificallyand efficiently catalyze endonucleolytic cleavage of sequences encodingHPDE.

Specific ribozyme cleavage sites within any potential RNA target areinitially identified by scanning the target molecule for ribozymecleavage sites, including the following sequences: GUA, GUU, and GUC.Once identified, short RNA sequences of between 15 and 20ribonucleotides, corresponding to the region of the target genecontaining the cleavage site, may be evaluated for secondary structuralfeatures which may render the oligonucleotide inoperable. Thesuitability of candidate targets may also be evaluated by testingaccessibility to hybridization with complementary oligonucleotides usingribonuclease protection assays.

Complementary ribonucleic acid molecules and ribozymes of the inventionmay be prepared by any method known in the art for the synthesis ofnucleic acid molecules. These include techniques for chemicallysynthesizing oligonucleotides such as solid phase phosphoramiditechemical synthesis. Alternatively, RNA molecules may be generated by invitro and in vivo transcription of DNA sequences encoding HPDE. Such DNAsequences may be incorporated into a wide variety of vectors withsuitable RNA polymerase promoters such as T7 or SP6. Alternatively,these cDNA constructs that synthesize complementary RNA, constitutivelyor inducibly, can be introduced into cell lines, cells, or tissues.

RNA molecules may be modified to increase intracellular stability andhalf-life. Possible modifications include, but are not limited to, theaddition of flanking sequences at the 5′ and/or 3′ ends of the molecule,or the use of phosphorothioate or 2′ O-methyl rather thanphosphodiesterase linkages within the backbone of the molecule. Thisconcept is inherent in the production of PNAs and can be extended in allof these molecules by the inclusion of nontraditional bases such asinosine, queosine, and wybutosine, as well as acetyl-, methyl-, thio-,and similarly modified forms of adenine, cytidine, guanine, thymine, anduridine which are not as easily recognized by endogenous endonucleases.

An additional embodiment of the invention encompasses a method forscreening for a compound which is effective in altering expression of apolynucleotide encoding HPDE. Compounds which may be effective inaltering expression of a specific polynucleotide may include, but arenot limited to, oligonucleotides, antisense oligonucleotides, triplehelix-forming oligonucleotides, transcription factors and otherpolypeptide transcriptional regulators, and non-macromolecular chemicalentities which are capable of interacting with specific polynucleotidesequences. Effective compounds may alter polynucleotide expression byacting as either inhibitors or promoters of polynucleotide expression.Thus, in the treatment of disorders associated with increased HPDEexpression or activity, a compound which specifically inhibitsexpression of the polynucleotide encoding HPDE may be therapeuticallyuseful, and in the treament of disorders associated with decreased HPDEexpression or activity, a compound which specifically promotesexpression of the polynucleotide encoding HPDE may be therapeuticallyuseful.

At least one, and up to a plurality, of test compounds may be screenedfor effectiveness in altering expression of a specific polynucleotide. Atest compound may be obtained by any method commonly known in the art,including chemical modification of a compound known to be effective inaltering polynucleotide expression; selection from an existing,commercially-available or proprietary library of naturally-occurring ornon-natural chemical compounds; rational design of a compound based onchemical and/or structural properties of the target polynucleotide; andselection from a library of chemical compounds created combinatoriallyor randomly. A sample comprising a polynucleotide encoding HPDE isexposed to at least one test compound thus obtained. The sample maycomprise, for example, an intact or permeabilized cell, or an in vitrocell-free or reconstituted biochemical system. Alterations in theexpression of a polynucleotide encoding HPDE are assayed by any methodcommonly known in the art. Typically, the expression of a specificnucleotide is detected by hybridization with a probe having a nucleotidesequence complementary to the sequence of the polynucleotide encodingHPDE. The amount of hybridization may be quantified, thus forming thebasis for a comparison of the expression of the polynucleotide both withand without exposure to one or more test compounds. Detection of achange in the expression of a polynucleotide exposed to a test compoundindicates that the test compound is effective in altering the expressionof the polynucleotide. A screen for a compound effective in alteringexpression of a specific polynucleotide can be carried out, for example,using a Schizosaccharomvces pombe gene expression system (Atkins, D. etal. (1999) U.S. Pat. No. 5,932,435; Arndt, G. M. et al. (2000) NucleicAcids Res. 28:E15) or a human cell line such as HeLa cell (Clarke, M. L.et al. (2000) Biochem. Biophys. Res. Commun. 268:8-13). A particularembodiment of the present invention involves screening a combinatoriallibrary of oligonucleotides (such as deoxyribonucleotides,ribonucleotides, peptide nucleic acids, and modified oligonucleotides)for antisense activity against a specific polynucleotide sequence(Bruice, T. W. et al. (1997) U.S. Pat. No. 5,686,242; Bruice, T. W. etal. (2000) U.S. Pat. No. 6,022,691).

Many methods for introducing vectors into cells or tissues are availableand equally suitable for use in vivo, in vitro, and ex vivo. For ex vivotherapy, vectors may be introduced into stem cells taken from thepatient and clonally propagated for autologous transplant back into thatsame patient. Delivery by transfection, by liposome injections, or bypolycationic amino polymers may be achieved using methods which are wellknown in the art. (See, e.g., Goldman, C. K. et al. (1997) Nat.Biotechnol. 15:462-466.)

Any of the therapeutic methods described above may be applied to anysubject in need of such therapy, including, for example, mammals such ashumans, dogs, cats, cows, horses, rabbits, and monkeys.

An additional embodiment of the invention relates to the administrationof a composition which generally comprises an active ingredientformulated with a pharmaceutically acceptable excipient. Excipients mayinclude, for example, sugars, starches, celluloses, gums, and proteins.Various formulations are commonly known and are thoroughly discussed inthe latest edition of Remington's Pharmaceutical Sciences (MaackPublishing, Easton Pa.). Such compositions may consist of HPDE,antibodies to HPDE, and mimetics, agonists, antagonists, or inhibitorsof HPDE.

The compositions utilized in this invention may be administered by anynumber of routes including, but not limited to, oral, intravenous,intramuscular, intra-arterial, intramedullary, intrathecal,intraventricular, pulmonary, transdermal, subcutaneous, intraperitoneal,intranasal, enteral, topical, sublingual, or rectal means.

Compositions for pulmonary administration may be prepared in liquid ordry powder form. These compositions are generally aerosolizedimmediately prior to inhalation by the patient. In the case of smallmolecules (e.g. traditional low molecular weight organic drugs), aerosoldelivery of fast-acting formulations is well-known in the art. In thecase of macromolecules (e.g. larger peptides and proteins), recentdevelopments in the field of pulmonary delivery via the alveolar regionof the lung have enabled the practical delivery of drugs such as insulinto blood circulation (see, e.g., Patton, J. S. et al., U.S. Pat. No.5,997,848). Pulmonary delivery has the advantage of administrationwithout needle injection, and obviates the need for potentially toxicpenetration enhancers.

Compositions suitable for use in the invention include compositionswherein the active ingredients are contained in an effective amount toachieve the intended purpose. The determination of an effective dose iswell within the capability of those skilled in the art.

Specialized forms of compositions may be prepared for directintracellular delivery of macromolecules comprising HPDE or fragmentsthereof. For example, liposome preparations containing acell-impermeable macromolecule may promote cell fusion and intracellulardelivery of the macromolecule. Alternatively, HPDE or a fragment thereofmay be joined to a short cationic N-terminal portion from the HIV Tat-1protein. Fusion proteins thus generated have been found to transduceinto the cells of all tissues, including the brain, in a mouse modelsystem (Schwarze, S. R. et al. (1999) Science 285:1569-1572).

For any compound, the therapeutically effective dose can be estimatedinitially either in cell culture assays, e.g., of neoplastic cells, orin animal models such as mice, rats, rabbits, dogs, monkeys, or pigs. Ananimal model may also be used to determine the appropriate concentrationrange and route of administration. Such information can then be used todetermine useful doses and routes for administration in humans.

A therapeutically effective dose refers to that amount of activeingredient, for example HPDE or fragments thereof, antibodies of HPDE,and agonists, antagonists or inhibitors of HPDE, which ameliorates thesymptoms or condition. Therapeutic efficacy and toxicity may bedetermined by standard pharmaceutical procedures in cell cultures orwith experimental animals, such as by calculating the ED₅₀ (the dosetherapeutically effective in 50% of the population) or LD₅₀ (the doselethal to 50% of the population) statistics. The dose ratio of toxic totherapeutic effects is the therapeutic index, which can be expressed asthe LD₅₀/ED₅₀ ratio. Compositions which exhibit large therapeuticindices are preferred. The data obtained from cell culture assays andanimal studies are used to formulate a range of dosage for human use.The dosage contained in such compositions is preferably within a rangeof circulating concentrations that includes the ED₅₀ with little or notoxicity. The dosage varies within this range depending upon the dosageform employed, the sensitivity of the patient, and the route ofadministration.

The exact dosage will be determined by the practitioner, in light offactors related to the subject requiring treatment. Dosage andadministration are adjusted to provide sufficient levels of the activemoiety or to maintain the desired effect. Factors which may be takeninto account include the severity of the disease state, the generalhealth of the subject, the age, weight, and gender of the subject, timeand frequency of administration, drug combination(s), reactionsensitivities, and response to therapy. Long-acting compositions may beadministered every 3 to 4 days, every week, or biweekly depending on thehalf-life and clearance rate of the particular formulation.

Normal dosage amounts may vary from about 0.1 μg to 100,000 μg, up to atotal dose of about 1 gram, depending upon the route of administration.Guidance as to particular dosages and methods of delivery is provided inthe literature and generally available to practitioners in the art.Those skilled in the art will employ different formulations fornucleotides than for proteins or their inhibitors. Similarly, deliveryof polynucleotides or polypeptides will be specific to particular cells,conditions, locations, etc.

Diagnostics

In another embodiment, antibodies which specifically bind HPDE may beused for the diagnosis of disorders characterized by expression of HPDE,or in assays to monitor patients being treated with HPDE or agonists,antagonists, or inhibitors of HPDE. Antibodies useful for diagnosticpurposes may be prepared in the same manner as described above fortherapeutics. Diagnostic assays for HPDE include methods which utilizethe antibody and a label to detect HPDE in human body fluids or inextracts of cells or tissues. The antibodies may be used with or withoutmodification, and may be labeled by covalent or non-covalent attachmentof a reporter molecule. A wide variety of reporter molecules, several ofwhich are described above, are known in the art and may be used.

A variety of protocols for measuring HPDE, including ELISAs, RIAs, andFACS, are known in the art and provide a basis for diagnosing altered orabnormal levels of HPDE expression. Normal or standard values for HPDEexpression are established by combining body fluids or cell extractstaken from normal mammalian subjects, for example, human subjects, withantibodies to HPDE under conditions suitable for complex formation. Theamount of standard complex formation may be quantitated by variousmethods, such as photometric means. Quantities of HPDE expressed insubject, control, and disease samples from biopsied tissues are comparedwith the standard values. Deviation between standard and subject valuesestablishes the parameters for diagnosing disease.

In another embodiment of the invention, the polynucleotides encodingHPDE may be used for diagnostic purposes. The polynucleotides which maybe used include oligonucleotide sequences, complementary RNA and DNAmolecules, and PNAs. The polynucleotides may be used to detect andquantify gene expression in biopsied tissues in which expression of HPDEmay be correlated with disease. The diagnostic assay may be used todetermine absence, presence, and excess expression of HPDE, and tomonitor regulation of HPDE levels during therapeutic intervention.

In one aspect, hybridization with PCR probes which are capable ofdetecting polynucleotide sequences, including genomic sequences,encoding HPDE or closely related molecules may be used to identifynucleic acid sequences which encode HPDE. The specificity of the probe,whether it is made from a highly specific region, e.g., the 5′regulatory region, or from a less specific region, e.g., a conservedmotif, and the stringency of the hybridization or amplification willdetermine whether the probe identifies only naturally occurringsequences encoding HPDE, allelic variants, or related sequences.

Probes may also be used for the detection of related sequences, and mayhave at least 50% sequence identity to any of the HPDE encodingsequences. The hybridization probes of the subject invention may be DNAor RNA and may be derived from the sequence of SEQ ID NO:4-6 or fromgenomic sequences including promoters, enhancers, and introns of theHPDE gene.

Means for producing specific hybridization probes for DNAs encoding HPDEinclude the cloning of polynucleotide sequences encoding HPDE or HPDEderivatives into vectors for the production of mRNA probes. Such vectorsare known in the art, are commercially available, and may be used tosynthesize RNA probes in vitro by means of the addition of theappropriate RNA polymerases and the appropriate labeled nucleotides.Hybridization probes may be labeled by a variety of reporter groups, forexample, by radionuclides such as ³²P or ³⁵S, or by enzymatic labels,such as alkaline phosphatase coupled to the probe via avidin/biotincoupling systems, and the like.

Polynucleotide sequences encoding HPDE may be used for the diagnosis ofdisorders associated with expression of HPDE. Examples of such disordersinclude, but are not limited to, an eye disorder, such asconjunctivitis, keratoconjunctivitis sicca, keratitis, episcleritis,iritis, posterior uveitis, glaucoma, amaurosis fugax, ischemic opticneuropathy, optic neuritis, Leber's hereditary optic neuropathy, toxicoptic neuropathy, vitreous detachment, retinal detachment, cataract,macular degeneration, central serous chorioretinopathy, retinitispigmentosa, melanoma of the choroid, retrobulbar tumor, and chiasmaltumor; a neurological disorder, such as epilepsy, ischemiccerebrovascular disease, stroke, cerebral neoplasms, Alzheimer'sdisease, Pick's disease, Huntington's disease, dementia, Parkinson'sdisease and other extrapyramidal disorders, amyotrophic lateralsclerosis and other motor neuron disorders, progressive neural muscularatrophy, retinitis pigmentosa, hereditary ataxias, multiple sclerosisand other demyelinating diseases, bacterial and viral meningitis, brainabscess, subdural empyema, epidural abscess, suppurative intracranialthrombophlebitis, myelitis and radiculitis, viral central nervous systemdisease, prion diseases including kuru, Creutzfeldt-Jakob disease, andGerstmann-Straussler-Scheinker syndrome, fatal familial insomnia,nutritional and metabolic diseases of the nervous system,neurofibromatosis, tuberous sclerosis, cerebelloretinalhemangioblastomatosis, encephalotrigeminal syndrome, mental retardationand other developmental disorders of the central nervous systemincluding Down syndrome, cerebral palsy, neuroskeletal disorders,autonomic nervous system disorders, cranial nerve disorders, spinal corddiseases, muscular dystrophy and other neuromuscular disorders,peripheral nervous system disorders, dermatomyositis and polymyositis,inherited, metabolic, endocrine, and toxic myopathies, myastheniagravis, periodic paralysis, mental disorders including mood, anxiety,and schizophrenic disorders, seasonal affective disorder (SAD),akathesia, amnesia, catatonia, diabetic neuropathy, tardive dyskinesia,dystonias, paranoid psychoses, postherpetic neuralgia, Tourette'sdisorder, progressive supranuclear palsy, corticobasal degeneration, andfamilial frontotemporal dementia; a cardiovascular disorder, such asarterioyenous fistula, atherosclerosis, hypertension, vasculitis,Raynaud's disease, aneurysms, arterial dissections, varicose veins,thrombophlebitis and phlebothrombosis, vascular tumors, andcomplications of thrombolysis, balloon angioplasty, vascularreplacement, and coronary artery bypass graft surgery, congestive heartfailure, ischemic heart disease, angina pectoris, myocardial infarction,hypertensive heart disease, degenerative valvular heart disease,calcific aortic valve stenosis, congenitally bicuspid aortic valve,mitral annular calcification, mitral valve prolapse, rheumatic fever andrheumatic heart disease, infective endocarditis, nonbacterial thromboticendocarditis, endocarditis of systemic lupus erythematosus, carcinoidheart disease, cardiomyopathy, myocarditis, pericarditis, neoplasticheart disease, congenital heart disease, and complications of cardiactransplantation, congenital lung anomalies, atelectasis, pulmonarycongestion and edema, pulmonary embolism, pulmonary hemorrhage,pulmonary infarction, pulmonary hypertension, vascular sclerosis,obstructive pulmonary disease, restrictive pulmonary disease, chronicobstructive pulmonary disease, emphysema, chronic bronchitis, bronchialasthma, bronchiectasis, bacterial pneumonia, viral and mycoplasmalpneumonia, lung abscess, pulmonary tuberculosis, diffuse interstitialdiseases, pneumoconioses, sarcoidosis, idiopathic pulmonary fibrosis,desquamative interstitial pneumonitis, hypersensitivity pneumonitis,pulmonary eosinophilia bronchiolitis obliterans-organizing pneumonia,diffuse pulmonary hemorrhage syndromes, Goodpasture's syndromes,idiopathic pulmonary hemosiderosis, pulmonary involvement incollagen-vascular disorders, pulmonary alveolar proteinosis, lungtumors, inflammatory and noninflammatory pleural effusions,pneumothorax, pleural tumors, drug-induced lung disease,radiation-induced lung disease, and complications of lungtransplantation; a cell proliferative disorder, such as actinickeratosis, arteriosclerosis, atherosclerosis, bursitis, cirrhosis,hepatitis, mixed connective tissue disease (MCTD), myelofibrosis,paroxysmal nocturnal hemoglobinuria, polycythemia vera, psoriasis,primary thrombocythemia, and cancers including adenocarcinoma, leukemia,lymphoma, melanoma, myeloma, sarcoma, teratocarcinoma, and, inparticular, cancers of the adrenal gland, bladder, bone, bone marrow,brain, breast, cervix, gall bladder, ganglia, gastrointestinal tract,heart, kidney, liver, lung, muscle, ovary, pancreas, parathyroid, penis,prostate, salivary glands, skin, spleen, testis, thymus, thyroid, anduterus; and an autoimmune/inflammatory disorder, acquiredimmunodeficiency syndrome (AIDS), Addison's disease, adult respiratorydistress syndrome, allergies, ankylosing spondylitis, amyloidosis,anemia, asthma, atherosclerosis, autoimmune hemolytic anemia, autoimmunethyroiditis, autoimmune polyendocrinopathy-candidiasis-ectodermaldystrophy (APECED), bronchitis, cholecystitis, contact dermatitis,Crohn's disease, atopic dermatitis, dermatomyositis, diabetes mellitus,emphysema, episodic lymphopenia with lymphocytotoxins, erythroblastosisfetalis, erythema nodosum, atrophic gastritis, glomerulonephritis,Goodpasture's syndrome, gout, Graves' disease, Hashimoto's thyroiditis,hypereosinophilia, irritable bowel syndrome, multiple sclerosis,myasthenia gravis, myocardial or pericardial inflammation,osteoarthritis, osteoporosis, pancreatitis, polymyositis, psoriasis,Reiter's syndrome, rheumatoid arthritis, scleroderma, Sjögren'ssyndrome, systemic anaphylaxis, systemic lupus erythematosus, systemicsclerosis, thrombocytopenic purpura, ulcerative colitis, uveitis, Wernersyndrome, complications of cancer, hemodialysis, and extracorporealcirculation, viral, bacterial, fungal, parasitic, protozoal, andhelminthic infections, and trauma. The polynucleotide sequences encodingHPDE may be used in Southern or northern analysis, dot blot, or othermembrane-based technologies; in PCR technologies; in dipstick, pin, andmultiformat ELISA-like assays; and in microarrays utilizing fluids ortissues from patients to detect altered HPDE expression. Suchqualitative or quantitative methods are well known in the art.

In a particular aspect, the nucleotide sequences encoding HPDE may beuseful in assays that detect the presence of associated disorders,particularly those mentioned above. The nucleotide sequences encodingHPDE may be labeled by standard methods and added to a fluid or tissuesample from a patient under conditions suitable for the formation ofhybridization complexes. After a suitable incubation period, the sampleis washed and the signal is quantified and compared with a standardvalue. If the amount of signal in the patient sample is significantlyaltered in comparison to control sample then the presence of alteredlevels of nucleotide sequences encoding HPDE in the sample indicates thepresence of the associated disorder. Such assays may also be used toevaluate the efficacy of a particular therapeutic treatment regimen inanimal studies, in clinical trials, or to monitor the treatment of anindividual patient.

In order to provide a basis for the diagnosis of a disorder associatedwith expression of HPDE, a normal or standard profile for expression isestablished. This may be accomplished by combining body fluids or cellextracts taken from normal subjects, either animal or human, with asequence, or a fragment thereof, encoding HPDE, under conditionssuitable for hybridization or amplification. Standard hybridization maybe quantified by comparing the values obtained from normal subjects withvalues from an experiment in which a known amount of a substantiallypurified polynucleotide is used. Standard values obtained in this mannermay be compared with values obtained from samples from patients who aresymptomatic for a disorder. Deviation from standard values is used toestablish the presence of a disorder.

Once the presence of a disorder is established and a treatment protocolis initiated, hybridization assays may be repeated on a regular basis todetermine if the level of expression in the patient begins toapproximate that which is observed in the normal subject. The resultsobtained from successive assays may be used to show the efficacy oftreatment over a period ranging from several days to months.

With respect to cancer, the presence of an abnormal amount of transcript(either under- or overexpressed) in biopsied tissue from an individualmay indicate a predisposition for the development of the disease, or mayprovide a means for detecting the disease prior to the appearance ofactual clinical symptoms. A more definitive diagnosis of this type mayallow health professionals to employ preventative measures or aggressivetreatment earlier thereby preventing the development or furtherprogression of the cancer.

Additional diagnostic uses for oligonucleotides designed from thesequences encoding HPDE may involve the use of PCR. These oligomers maybe chemically synthesized, generated enzymatically, or produced invitro. Oligomers will preferably contain a fragment of a polynucleotideencoding HPDE, or a fragment of a polynucleotide complementary to thepolynucleotide encoding HPDE, and will be employed under optimizedconditions for identification of a specific gene or condition. Oligomersmay also be employed under less stringent conditions for detection orquantification of closely related DNA or RNA sequences.

In a particular aspect, oligonucleotide primers derived from thepolynucleotide sequences encoding HPDE may be used to detect singlenucleotide polymorphisms (SNPs). SNPs are substitutions, insertions anddeletions that are a frequent cause of inherited or acquired geneticdisease in humans. Methods of SNP detection include, but are not limitedto, single-stranded conformation polymorphism (SSCP) and fluorescentSSCP (fSSCP) methods. In SSCP, oligonucleotide primers derived from thepolynucleotide sequences encoding HPDE are used to amplify DNA using thepolymerase chain reaction (PCR). The DNA may be derived, for example,from diseased or normal tissue, biopsy samples, bodily fluids, and thelike. SNPs in the DNA cause differences in the secondary and tertiarystructures of PCR products in single-stranded form, and thesedifferences are detectable using gel electrophoresis in non-denaturinggels. In fSCCP, the oligonucleotide primers are fluorescently labeled,which allows detection of the amplimers in high-throughput equipmentsuch as DNA sequencing machines. Additionally, sequence databaseanalysis methods, termed in silico SNP (isSNP), are capable ofidentifying polymorphisms by comparing the sequence of individualoverlapping DNA fragments which assemble into a common consensussequence. These computer-based methods filter out sequence variationsdue to laboratory preparation of DNA and sequencing errors usingstatistical models and automated analyses of DNA sequence chromatograms.In the alternative, SNPs may be detected and characterized by massspectrometry using, for example, the high throughput MASSARRAY system(Sequenom, Inc., San Diego Calif.).

Methods which may also be used to quantify the expression of HPDEinclude radiolabeling or biotinylating nucleotides, coamplification of acontrol nucleic acid, and interpolating results from standard curves.(See, e.g., Melby, P. C. et al. (1993) J. Immunol. Methods 159:235-244;Duplaa, C. et al. (1993) Anal. Biochem. 212:229-236.) The speed ofquantitation of multiple samples may be accelerated by running the assayin a high-throughput format where the oligomer or polynucleotide ofinterest is presented in various dilutions and a spectrophotometric orcolorimetric response gives rapid quantitation.

In further embodiments, oligonucleotides or longer fragments derivedfrom any of the polynucleotide sequences described herein may be used aselements on a microarray. The microarray can be used in transcriptimaging techniques which monitor the relative expression levels of largenumbers of genes simultaneously as described below. The microarray mayalso be used to identify genetic variants, mutations, and polymorphisms.This information may be used to determine gene function, to understandthe genetic basis of a disorder, to diagnose a disorder, to monitorprogression/regression of disease as a function of gene expression, andto develop and monitor the activities of therapeutic agents in thetreatment of disease. In particular, this information may be used todevelop a pharmacogenomic profile of a patient in order to select themost appropriate and effective treatment regimen for that patient. Forexample, therapeutic agents which are highly effective and display thefewest side effects may be selected for a patient based on his/herpharmacogenomic profile.

In another embodiment, HPDE, fragments of HPDE, or antibodies specificfor HPDE may be used as elements on a microarray. The microarray may beused to monitor or measure protein-protein interactions, drug-targetinteractions, and gene expression profiles, as described above.

A particular embodiment relates to the use of the polynucleotides of thepresent invention to generate a transcript image of a tissue or celltype. A transcript image represents the global pattern of geneexpression by a particular tissue or cell type. Global gene expressionpatterns are analyzed by quantifying the number of expressed genes andtheir relative abundance under given conditions and at a given time.(See Seilhamer et al., “Comparative Gene Transcript Analysis,” U.S. Pat.No. 5,840,484, expressly incorporated by reference herein.) Thus atranscript image may be generated by hybridizing the polynucleotides ofthe present invention or their complements to the totality oftranscripts or reverse transcripts of a particular tissue or cell type.In one embodiment, the hybridization takes place in high-throughputformat, wherein the polynucleotides of the present invention or theircomplements comprise a subset of a plurality of elements on amicroarray. The resultant transcript image would provide a profile ofgene activity.

Transcript images may be generated using transcripts isolated fromtissues, cell lines, biopsies, or other biological samples. Thetranscript image may thus reflect gene expression in vivo, as in thecase of a tissue or biopsy sample, or in vitro, as in the case of a cellline.

Transcript images which profile the expression of the polynucleotides ofthe present invention may also be used in conjunction with in vitromodel systems and preclinical evaluation of pharmaceuticals, as well astoxicological testing of industrial and naturally-occurringenvironmental compounds. All compounds induce characteristic geneexpression patterns, frequently termed molecular fingerprints ortoxicant signatures, which are indicative of mechanisms of action andtoxicity (Nuwaysir, E. F. et al. (1999) Mol. Carcinog. 24:153-159;Steiner, S. and N. L. Anderson (2000) Toxicol. Lett. 112-113:467-471,expressly incorporated by reference herein). If a test compound has asignature similar to that of a compound with known toxicity, it islikely to share those toxic properties. These fingerprints or signaturesare most useful and refined when they contain expression informationfrom a large number of genes and gene families. Ideally, a genome-widemeasurement of expression provides the highest quality signature. Evengenes whose expression is not altered by any tested compounds areimportant as well, as the levels of expression of these genes are usedto normalize the rest of the expression data. The normalizationprocedure is useful for comparison of expression data after treatmentwith different compounds. While the assignment of gene function toelements of a toxicant signature aids in interpretation of toxicitymechanisms, knowledge of gene function is not necessary for thestatistical matching of signatures which leads to prediction oftoxicity. (See, for example, Press Release 00-02 from the NationalInstitute of Environmental Health Sciences, released Feb. 29, 2000,available at http://www.niehs.nih.gov/oc/news/toxchip.htm.) Therefore,it is important and desirable in toxicological screening using toxicantsignatures to include all expressed gene sequences.

In one embodiment, the toxicity of a test compound is assessed bytreating a biological sample containing nucleic acids with the testcompound. Nucleic acids that are expressed in the treated biologicalsample are hybridized with one or more probes specific to thepolynucleotides of the present invention, so that transcript levelscorresponding to the polynucleotides of the present invention may bequantified. The transcript levels in the treated biological sample arecompared with levels in an untreated biological sample. Differences inthe transcript levels between the two samples are indicative of a toxicresponse caused by the test compound in the treated sample.

Another particular embodiment relates to the use of the polypeptidesequences of the present invention to analyze the proteome of a tissueor cell type. The term proteome refers to the global pattern of proteinexpression in a particular tissue or cell type. Each protein componentof a proteome can be subjected individually to further analysis.Proteome expression patterns, or profiles, are analyzed by quantifyingthe number of expressed proteins and their relative abundance undergiven conditions and at a given time. A profile of a cell's proteome maythus be generated by separating and analyzing the polypeptides of aparticular tissue or cell type. In one embodiment, the separation isachieved using two-dimensional gel electrophoresis, in which proteinsfrom a sample are separated by isoelectric focusing in the firstdimension, and then according to molecular weight by sodium dodecylsulfate slab gel electrophoresis in the second dimension (Steiner andAnderson, supra). The proteins are visualized in the gel as discrete anduniquely positioned spots, typically by staining the gel with an agentsuch as Coomassie Blue or silver or fluorescent stains. The opticaldensity of each protein spot is generally proportional to the level ofthe protein in the sample. The optical densities of equivalentlypositioned protein spots from different samples, for example, frombiological samples either treated or untreated with a test compound ortherapeutic agent, are compared to identify any changes in protein spotdensity related to the treatment. The proteins in the spots arepartially sequenced using, for example, standard methods employingchemical or enzymatic cleavage followed by mass spectrometry. Theidentity of the protein in a spot may be determined by comparing itspartial sequence, preferably of at least 5 contiguous amino acidresidues, to the polypeptide sequences of the present invention. In somecases, further sequence data may be obtained for definitive proteinidentification.

A proteomic profile may also be generated using antibodies specific forHPDE to quantify the levels of HPDE expression. In one embodiment, theantibodies are used as elements on a microarray, and protein expressionlevels are quantified by exposing the microarray to the sample anddetecting the levels of protein bound to each array element (Lueking, A.et al. (1999) Anal. Biochem. 270:103-111; Mendoze, L. G. et al. (1999)Biotechniques 27:778-788). Detection may be performed by a variety ofmethods known in the art, for example, by reacting the proteins in thesample with a thiol- or amino-reactive fluorescent compound anddetecting the amount of fluorescence bound at each array element.

Toxicant signatures at the proteome level are also useful fortoxicological screening, and should be analyzed in parallel withtoxicant signatures at the transcript level. There is a poor correlationbetween transcript and protein abundances for some proteins in sometissues (Anderson, N. L. and J. Seilhamer (1997) Electrophoresis18:533-537), so proteome toxicant signatures may be useful in theanalysis of compounds which do not significantly affect the transcriptimage, but which alter the proteomic profile. In addition, the analysisof transcripts in body fluids is difficult, due to rapid degradation ofmRNA, so proteomic profiling may be more reliable and informative insuch cases.

In another embodiment, the toxicity of a test compound is assessed bytreating a biological sample containing proteins with the test compound.Proteins that are expressed in the treated biological sample areseparated so that the amount of each protein can be quantified. Theamount of each protein is compared to the amount of the correspondingprotein in an untreated biological sample. A difference in the amount ofprotein between the two samples is indicative of a toxic response to thetest compound in the treated sample. Individual proteins are identifiedby sequencing the amino acid residues of the individual proteins andcomparing these partial sequences to the polypeptides of the presentinvention.

In another embodiment, the toxicity of a test compound is assessed bytreating a biological sample containing proteins with the test compound.Proteins from the biological sample are incubated with antibodiesspecific to the polypeptides of the present invention. The amount ofprotein recognized by the antibodies is quantified. The amount ofprotein in the treated biological sample is compared with the amount inan untreated biological sample. A difference in the amount of proteinbetween the two samples is indicative of a toxic response to the testcompound in the treated sample.

Microarrays may be prepared, used, and analyzed using methods known inthe art. (See, e.g., Brennan, T. M. et al. (1995) U.S. Pat. No.5,474,796; Schena, M. et al. (1996) Proc. Natl. Acad. Sci. USA93:10614-10619; Baldeschweiler et al. (1995) PCT applicationWO95/251116; Shalon, D. et al. (1995) PCT application WO95/35505;Heller, R. A. et al. (1997) Proc. Natl. Acad. Sci. USA 94:2150-2155; andHeller, M. J. et al. (1997) U.S. Pat. No. 5,605,662.) Various types ofmicroarrays are well known and thoroughly described in DNA Microarrays:A Practical Approach, M. Schena, ed. (1999) Oxford University Press,London, hereby expressly incorporated by reference.

In another embodiment of the invention, nucleic acid sequences encodingHPDE may be used to generate hybridization probes useful in mapping thenaturally occurring genomic sequence. Either coding or noncodingsequences may be used, and in some instances, noncoding sequences may bepreferable over coding sequences. For example, conservation of a codingsequence among members of a multi-gene family may potentially causeundesired cross hybridization during chromosomal mapping. The sequencesmay be mapped to a particular chromosome, to a specific region of achromosome, or to artificial chromosome constructions, e.g., humanartificial chromosomes (HACs), yeast artificial chromosomes (YACs),bacterial artificial chromosomes (BACs), bacterial P1 constructions, orsingle chromosome cDNA libraries. (See, e.g., Harrington, J. J. et al.(1997) Nat. Genet. 15:345-355; Price, C. M. (1993) Blood Rev. 7:127-134;and Trask, B. J. (1991) Trends Genet. 7:149-154.) Once mapped, thenucleic acid sequences of the invention may be used to develop geneticlinkage maps, for example, which correlate the inheritance of a diseasestate with the inheritance of a particular chromosome region orrestriction fragment length polymorphism (RFLP). (See, for example,Lander, E. S. and D. Botstein (1986) Proc. Natl. Acad. Sci. USA83:7353-7357.)

Fluorescent in situ hybridization (FISH) may be correlated with otherphysical and genetic map data. (See, e.g., Heinz-Ulrich, et al. (1995)in Meyers, supra, pp. 965-968.) Examples of genetic map data can befound in various scientific journals or at the Online MendelianInheritance in Man (OMIM) World Wide Web site. Correlation between thelocation of the gene encoding HPDE on a physical map and a specificdisorder, or a predisposition to a specific disorder, may help definethe region of DNA associated with that disorder and thus may furtherpositional cloning efforts.

In situ hybridization of chromosomal preparations and physical mappingtechniques, such as linkage analysis using established chromosomalmarkers, may be used for extending genetic maps. Often the placement ofa gene on the chromosome of another mammalian species, such as mouse,may reveal associated markers even if the exact chromosomal locus is notknown. This information is valuable to investigators searching fordisease genes using positional cloning or other gene discoverytechniques. Once the gene or genes responsible for a disease or syndromehave been crudely localized by genetic linkage to a particular genomicregion, e.g., ataxia-telangiectasia to 11q22-23, any sequences mappingto that area may represent associated or regulatory genes for furtherinvestigation. (See, e.g., Gatti, R. A. et al. (1988) Nature336:577-580.) The nucleotide sequence of the instant invention may alsobe used to detect differences in the chromosomal location due totranslocation, inversion, etc., among normal, carrier, or affectedindividuals.

In another embodiment of the invention, HPDE, its catalytic orimmunogenic fragments, or oligopeptides thereof can be used forscreening libraries of compounds in any of a variety of drug screeningtechniques. The fragment employed in such screening may be free insolution, affixed to a solid support, borne on a cell surface, orlocated intracellularly. The formation of binding complexes between HPDEand the agent being tested may be measured.

Another technique for drug screening provides for high throughputscreening of compounds having suitable binding affinity to the proteinof interest. (See, e.g., Geysen, et al. (1984) PCT applicationWO84/03564.) In this method, large numbers of different small testcompounds are synthesized on a solid substrate. The test compounds arereacted with HPDE, or fragments thereof, and washed. Bound HPDE is thendetected by methods well known in the art. Purified HPDE can also becoated directly onto plates for use in the aforementioned drug screeningtechniques. Alternatively, non-neutralizing antibodies can be used tocapture the peptide and immobilize it on a solid support.

In another embodiment, one may use competitive drug screening assays inwhich neutralizing antibodies capable of binding HPDE specificallycompete with a test compound for binding HPDE. In this manner,antibodies can be used to detect the presence of any peptide whichshares one or more antigenic determinants with HPDE.

In additional embodiments, the nucleotide sequences which encode HPDEmay be used in any molecular biology techniques that have yet to bedeveloped, provided the new techniques rely on properties of nucleotidesequences that are currently known, including, but not limited to, suchproperties as the triplet genetic code and specific base pairinteractions.

Without further elaboration, it is believed that one skilled in the artcan, using the preceding description, utilize the present invention toits fullest extent. The following embodiments are, therefore, to beconstrued as merely illustrative, and not limitative of the remainder ofthe disclosure in any way whatsoever.

The disclosures of all patents, applications and publications, mentionedabove and below, in particular U.S. Ser. No. 60/178,570, U.S. Ser. No.60/182,042, and U.S. Ser. No. 60/183,178, are expressly incorporated byreference herein.

EXAMPLES

I. Construction of cDNA Libraries

Incyte cDNAs were derived from cDNA libraries described in the LIFESEQGOLD database (Incyte Genomics, Palo Alto Calif.) and shown in Table 4,column 5. Some tissues were homogenized and lysed in guanidiniumisothiocyanate, while others were homogenized and lysed in phenol or ina suitable mixture of denaturants, such as TRIZOL (Life Technologies), amonophasic solution of phenol and guanidine isothiocyanate. Theresulting lysates were centrifuged over CsCl cushions or extracted withchloroform. RNA was precipitated from the lysates with eitherisopropanol or sodium acetate and ethanol, or by other routine methods.

Phenol extraction and precipitation of RNA were repeated as necessary toincrease RNA purity. In some cases, RNA was treated with DNase. For mostlibraries, poly(A)+ RNA was isolated using oligo d(T)-coupledparamagnetic particles (Promega), OLIGOTEX latex particles (QIAGEN,Chatsworth Calif.), or an OLIGOTEX mRNA purification kit (QIAGEN).Alternatively, RNA was isolated directly from tissue lysates using otherRNA isolation kits, e.g., the POLY(A)PURE mRNA purification kit (Ambion,Austin Tex.).

In some cases, Stratagene was provided with RNA and constructed thecorresponding cDNA libraries. Otherwise, cDNA was synthesized and cDNAlibraries were constructed with the UNIZAP vector system (Stratagene) orSUPERSCRIPT plasmid system (Life Technologies), using the recommendedprocedures or similar methods known in the art. (See, e.g., Ausubel,1997, supra, units 5.1-6.6.) Reverse transcription was initiated usingoligo d(T) or random primers. Synthetic oligonucleotide adapters wereligated to double stranded cDNA, and the cDNA was digested with theappropriate restriction enzyme or enzymes. For most libraries, the cDNAwas size-selected (300-1000 bp) using SEPHACRYL S1000, SEPHAROSE CL2B,or SEPHAROSE CL4B column chromatography (Amersham Pharmacia Biotech) orpreparative agarose gel electrophoresis. cDNAs were ligated intocompatible restriction enzyme sites of the polylinker of a suitableplasmid, e.g., PBLUESCRIPT plasmid (Stratagene), PSPORT1 plasmid (LifeTechnologies), PCDNA2.1 plasmid (Invitrogen, Carlsbad Calif.), PBK-CMVplasmid (Stratagene), or pINCY (Incyte Genomics, Palo Alto Calif.), orderivatives thereof. Recombinant plasmids were transformed intocompetent E. coli cells including XL1-Blue, XL 1-BlueMRF, or SOLR fromStratagene or DH5α, DH10B, or ElectroMAX DH10B from Life Technologies.

II. Isolation of cDNA Clones

Plasmids obtained as described in Example I were recovered from hostcells by in vivo excision using the UNIZAP vector system (Stratagene) orby cell lysis. Plasmids were purified using at least one of thefollowing: a Magic or WIZARD Minipreps DNA purification system(Promega); an AGTC Miniprep purification kit (Edge Biosystems,Gaithersburg Md.); and QIAWELL 8 Plasmid, QIAWELL 8 Plus Plasmid,QIAWELL 8 Ultra Plasmid purification systems or the R.E.A.L. PREP 96plasmid purification kit from QIAGEN. Following precipitation, plasmidswere resuspended in 0.1 ml of distilled water and stored, with orwithout lyophilization, at 4° C.

Alternatively, plasmid DNA was amplified from host cell lysates usingdirect link PCR in a high-throughput format (Rao, V. B. (1994) Anal.Biochem. 216:1-14). Host cell lysis and thermal cycling steps werecarried out in a single reaction mixture. Samples were processed andstored in 384-well plates, and the concentration of amplified plasmidDNA was quantified fluorometrically using PICOGREEN dye (MolecularProbes, Eugene Oreg.) and a FLUOROSKAN II fluorescence scanner(Labsystems Oy, Helsinki, Finland).

III. Sequencing and Analysis

Incyte cDNA recovered in plasmids as described in Example II weresequenced as follows. Sequencing reactions were processed using standardmethods or high-throughput instrumentation such as the ABI CATALYST 800(Applied Biosystems) thermal cycler or the PTC-200 thermal cycler (MJResearch) in conjunction with the HYDRA microdispenser (RobbinsScientific) or the MICROLAB 2200 (Hamilton) liquid transfer system. cDNAsequencing reactions were prepared using reagents provided by AmershamPharmacia Biotech or supplied in ABI sequencing kits such as the ABIPRISM BIGDYE Terminator cycle sequencing ready reaction kit (AppliedBiosystems). Electrophoretic separation of cDNA sequencing reactions anddetection of labeled polynucleotides were carried out using the MEGABACE1000 DNA sequencing system (Molecular Dynamics); the ABI PRISM 373 or377 sequencing system (Applied Biosystems) in conjunction with standardABI protocols and base calling software; or other sequence analysissystems known in the art. Reading frames within the cDNA sequences wereidentified using standard methods (reviewed in Ausubel, 1997, supra,unit 7.7). Some of the cDNA sequences were selected for extension usingthe techniques disclosed in Example VIII.

The polynucleotide sequences derived from Incyte cDNAs were validated byremoving vector, linker, and poly(A) sequences and by masking ambiguousbases, using algorithms and programs based on BLAST, dynamicprogramming, and dinucleotide nearest neighbor analysis. The Incyte cDNAsequences or translations thereof were then queried against a selectionof public databases such as the GenBank primate, rodent, mammalian,vertebrate, and eukaryote databases, and BLOCKS, PRINTS, DOMO, PRODOM,and hidden Markov model (HMM)-based protein family databases such asPFAM. (HMM is a probabilistic approach which analyzes consensus primarystructures of gene families. See, for example, Eddy, S.R. (1996) Curr.Opin. Struct. Biol. 6:361-365.) The queries were performed usingprograms based on BLAST, FASTA, BLIMPS, and HMMER. The Incyte cDNAsequences were assembled to produce full length polynucleotidesequences. Alternatively, GenBank cDNAs, GenBank ESTs, stitchedsequences, stretched sequences, or Genscan-predicted coding sequences(see Examples IV and V) were used to extend Incyte cDNA assemblages tofull length. Assembly was performed using programs based on Phred,Phrap, and Consed, and cDNA assemblages were screened for open readingframes using programs based on GeneMark, BLAST, and FASTA. The fulllength polynucleotide sequences were translated to derive thecorresponding full length polypeptide sequences. Alternatively, apolypeptide of the invention may begin at any of the methionine residuesof the full length translated polypeptide. Full length polypeptidesequences were subsequently analyzed by querying against databases suchas the GenBank protein databases (genpept), SwissProt, BLOCKS, PRINTS,DOMO, PRODOM, Prosite, and hidden Markov model (HMM)-based proteinfamily databases such as PFAM. Full length polynucleotide sequences arealso analyzed using MACDNASIS PRO software (Hitachi SoftwareEngineering, South San Francisco Calif.) and LASERGENE software(DNASTAR). Polynucleotide and polypeptide sequence alignments aregenerated using default parameters specified by the CLUSTAL algorithm asincorporated into the MEGALIGN multisequence alignment program(DNASTAR), which also calculates the percent identity between alignedsequences.

Table 7 summarizes the tools, programs, and algorithms used for theanalysis and assembly of Incyte cDNA and full length sequences andprovides applicable descriptions, references, and threshold parameters.The first column of Table 7 shows the tools, programs, and algorithmsused, the second column provides brief descriptions thereof, the thirdcolumn presents appropriate references, all of which are incorporated byreference herein in their entirety, and the fourth column presents,where applicable, the scores, probability values, and other parametersused to evaluate the strength of a match between two sequences (thehigher the score or the lower the probability value, the greater theidentity between two sequences).

The programs described above for the assembly and analysis of fulllength polynucleotide and polypeptide sequences were also used toidentify polynucleotide sequence fragments from SEQ ID NO:4-6. Fragmentsfrom about 20 to about 4000 nucleotides which are useful inhybridization and amplification technologies are described in Table 4,column 4.

IV. Identification and Editing of Coding Sequences from Genomic DNA

Putative phosphodiesterases were initially identified by running theGenscan gene identification program against public genomic sequencedatabases (e.g., gbpri and gbhtg). Genscan is a general-purpose geneidentification program which analyzes genomic DNA sequences from avariety of organisms (See Burge, C. and S. Karlin (1997) J. Mol. Biol.268:78-94, and Burge, C. and S. Karlin (1998) Curr. Opin. Struct. Biol.8:346-354). The program concatenates predicted exons to form anassembled cDNA sequence extending from a methionine to a stop codon. Theoutput of Genscan is a FASTA database of polynucleotide and polypeptidesequences. The maximum range of sequence for Genscan to analyze at oncewas set to 30 kb. To determine which of these Genscan predicted cDNAsequences encode phosphodiesterases, the encoded polypeptides wereanalyzed by querying against PFAM models for phosphodiesterases.Potential phosphodiesterases were also identified by homology to IncytecDNA sequences that had been annotated as phosphodiesterases. Theseselected Genscan-predicted sequences were then compared by BLASTanalysis to the genpept and gbpri public databases. Where necessary, theGenscan-predicted sequences were then edited by comparison to the topBLAST hit from genpept to correct errors in the sequence predicted byGenscan, such as extra or omitted exons. BLAST analysis was also used tofind any Incyte cDNA or public cDNA coverage of the Genscan-predictedsequences, thus providing evidence for transcription. When Incyte cDNAcoverage was available, this information was used to correct or confirmthe Genscan predicted sequence. Full length polynucleotide sequenceswere obtained by assembling Genscan-predicted coding sequences withIncyte cDNA sequences and/or public cDNA sequences using the assemblyprocess described in Example III. Alternatively, full lengthpolynucleotide sequences were derived entirely from edited or uneditedGenscan-predicted coding sequences.

V. Assembly of Genomic Sequence Data with cDNA Sequence Data

“Stitched” Sequences

Partial cDNA sequences were extended with exons predicted by the Genscangene identification program described in Example IV. Partial cDNAsassembled as described in Example III were mapped to genomic DNA andparsed into clusters containing related cDNAs and Genscan exonpredictions from one or more genomic sequences. Each cluster wasanalyzed using an algorithm based on graph theory and dynamicprogramming to integrate cDNA and genomic information, generatingpossible splice variants that were subsequently confirmed, edited, orextended to create a full length sequence. Sequence intervals in whichthe entire length of the interval was present on more than one sequencein the cluster were identified, and intervals thus identified wereconsidered to be equivalent by transitivity. For example, if an intervalwas present on a cDNA and two genomic sequences, then all threeintervals were considered to be equivalent. This process allowsunrelated but consecutive genomic sequences to be brought together,bridged by cDNA sequence. Intervals thus identified were then “stitched”together by the stitching algorithm in the order that they appear alongtheir parent sequences to generate the longest possible sequence, aswell as sequence variants. Linkages between intervals which proceedalong one type of parent sequence (cDNA to cDNA or genomic sequence togenomic sequence) were given preference over linkages which changeparent type (cDNA to genomic sequence). The resultant stitched sequenceswere translated and compared by BLAST analysis to the genpept and gbpripublic databases. Incorrect exons predicted by Genscan were corrected bycomparison to the top BLAST hit from genpept. Sequences were furtherextended with additional cDNA sequences, or by inspection of genomicDNA, when necessary.

“Stretched” Sequences

Partial DNA sequences were extended to full length with an algorithmbased on BLAST analysis. First, partial cDNAs assembled as described inExample III were queried against public databases such as the GenBankprimate, rodent, mammalian, vertebrate, and eukaryote databases usingthe BLAST program. The nearest GenBank protein homolog was then comparedby BLAST analysis to either Incyte cDNA sequences or GenScan exonpredicted sequences described in Example IV. A chimeric protein wasgenerated by using the resultant high-scoring segment pairs (HSPs) tomap the translated sequences onto the GenBank protein homolog.Insertions or deletions may occur in the chimeric protein with respectto the original GenBank protein homolog. The GenBank protein homolog,the chimeric protein, or both were used as probes to search forhomologous genomic sequences from the public human genome databases.Partial DNA sequences were therefore “stretched” or extended by theaddition of homologous genomic sequences. The resultant stretchedsequences were examined to determine whether it contained a completegene.

VI. Chromosomal Mapping of HPDE Encoding Polynucleotides

The sequences which were used to assemble SEQ ID NO:4-6 were comparedwith sequences from the Incyte LIFESEQ database and public domaindatabases using BLAST and other implementations of the Smith-Watermanalgorithm. Sequences from these databases that matched SEQ ID NO:4-6were assembled into clusters of contiguous and overlapping sequencesusing assembly algorithms such as Phrap (Table 7). Radiation hybrid andgenetic mapping data available from public resources such as theStanford Human Genome Center (SHGC), Whitehead Institute for GenomeResearch (WIGR), and Généthon were used to determine if any of theclustered sequences had been previously mapped. Inclusion of a mappedsequence in a cluster resulted in the assignment of all sequences ofthat cluster, including its particular SEQ ID NO:, to that map location.

Map locations are represented by ranges, or intervals, or humanchromosomes. The map position of an interval, in centiMorgans, ismeasured relative to the terminus of the chromosome's p-arm. (ThecentiMorgan (cM) is a unit of measurement based on recombinationfrequencies between chromosomal markers. On average, 1 cM is roughlyequivalent to 1 megabase (Mb) of DNA in humans, although this can varywidely due to hot and cold spots of recombination.) The cM distances arebased on genetic markers mapped by Généthon which provide boundaries forradiation hybrid markers whose sequences were included in each of theclusters. Human genome maps and other resources available to the public,such as the NCBI “GeneMap'99” World Wide Web site(http://www.ncbi.nlm.nih.gov/genemap/), can be employed to determine ifpreviously identified disease genes map within or in proximity to theintervals indicated above.

VII. Analysis of Polynucleotide Expression

Northern analysis is a laboratory technique used to detect the presenceof a transcript of a gene and involves the hybridization of a labelednucleotide sequence to a membrane on which RNAs from a particular celltype or tissue have been bound. (See, e.g., Sambrook, supra, ch. 7;Ausubel (1995) supra, ch. 4 and 16.)

Analogous computer techniques applying BLAST were used to search foridentical or related molecules in cDNA databases such as GenBank orLIFESEQ (Incyte Genomics). This analysis is much faster than multiplemembrane-based hybridizations. In addition, the sensitivity of thecomputer search can be modified to determine whether any particularmatch is categorized as exact or similar. The basis of the search is theproduct score, which is defined as:$\frac{{BLAST}\quad{Score}\quad \times \quad{Percent}\quad{Identity}}{5 \times \quad{minimum}\left\{ {{{length}\left( {{Seq}.\quad 1} \right)},{{length}\left( {{Seq}.\quad 2} \right)}} \right\}}$The product score takes into account both the degree of similaritybetween two sequences and the length of the sequence match. The productscore is a normalized value between 0 and 100, and is calculated asfollows: the BLAST score is multiplied by the percent nucleotideidentity and the product is divided by (5 times the length of theshorter of the two sequences). The BLAST score is calculated byassigning a score of +5 for every base that matches in a high-scoringsegment pair (HSP), and −4 for every mismatch. Two sequences may sharemore than one HSP (separated by gaps). If there is more than one HSP,then the pair with the highest BLAST score is used to calculate theproduct score. The product score represents a balance between fractionaloverlap and quality in a BLAST alignment. For example, a product scoreof 100 is produced only for 100% identity over the entire length of theshorter of the two sequences being compared. A product score of 70 isproduced either by 100% identity and 70% overlap at one end, or by 88%identity and 100% overlap at the other. A product score of 50 isproduced either by 100% identity and 50% overlap at one end, or 79%identity and 100% overlap.

Alternatively, polynucleotide sequences encoding HPDE are analyzed withrespect to the tissue sources from which they were derived. For example,some full length sequences are assembled, at least in part, withoverlapping Incyte cDNA sequences (see Example III). Each cDNA sequenceis derived from a cDNA library constructed from a human tissue. Eachhuman tissue is classified into one of the following organ/tissuecategories: cardiovascular system; connective tissue; digestive system;embryonic structures; endocrine system; exocrine glands; genitalia,female; genitalia, male; germ cells; hemic and immune system; liver;musculoskeletal system; nervous system; pancreas; respiratory system;sense organs; skin; stomatognathic system; unclassified/mixed; orurinary tract. The number of libraries in each category is counted anddivided by the total number of libraries across all categories.Similarly, each human tissue is classified into one of the followingdisease/condition categories: cancer, cell line, developmental,inflammation, neurological, trauma, cardiovascular, pooled, and other,and the number of libraries in each category is counted and divided bythe total number of libraries across all categories. The resultingpercentages reflect the tissue- and disease-specific expression of cDNAencoding HPDE. cDNA sequences and cDNA library/tissue information arefound in the LIFESEQ GOLD database (Incyte Genomics, Palo Alto Calif.).

VIII. Extension of HPDE Encoding Polynucleotides

Full length polynucleotide sequences were also produced by extension ofan appropriate fragment of the full length molecule usingoligonucleotide primers designed from this fragment. One primer wassynthesized to initiate 5′ extension of the known fragment, and theother primer was synthesized to initiate 3′ extension of the knownfragment. The initial primers were designed using OLIGO 4.06 software(National Biosciences), or another appropriate program, to be about 22to 30 nucleotides in length, to have a GC content of about 50% or more,and to anneal to the target sequence at temperatures of about 68° C. toabout 72° C. Any stretch of nucleotides which would result in hairpinstructures and primer-primer dimerizations was avoided.

Selected human cDNA libraries were used to extend the sequence. If morethan one extension was necessary or desired, additional or nested setsof primers were designed.

High fidelity amplification was obtained by PCR using methods well knownin the art. PCR was performed in 96-well plates using the PTC-200thermal cycler (MJ Research, Inc.). The reaction mix contained DNAtemplate, 200 nmol of each primer, reaction buffer containing Mg²⁺,(NH₄)₂SO₄, and 2-mercaptoethanol, Taq DNA polymerase (Amersham PharmaciaBiotech), ELONGASE enzyme (Life Technologies), and Pfu DNA polymerase(Stratagene), with the following parameters for primer pair PCI A andPCI B: Step 1: 94° C., 3 min; Step 2: 94° C., 15 sec; Step 3: 60° C., 1min; Step 4: 68° C., 2 min; Step 5: Steps 2, 3, and 4 repeated 20 times;Step 6: 68° C., 5 min; Step 7: storage at 4° C. In the alternative, theparameters for primer pair T7 and SK+ were as follows: Step 1: 94° C., 3min; Step 2: 94° C., 15 sec; Step 3: 57° C., 1 min; Step 4: 68° C., 2min; Step 5: Steps 2, 3, and 4 repeated 20 times; Step 6: 68° C., 5 min;Step 7: storage at 4° C.

The concentration of DNA in each well was determined by dispensing 100μl PICOGREEN quantitation reagent (0.25% (v/v) PICOGREEN; MolecularProbes, Eugene Oreg.) dissolved in 1×TE and 0.5 μl of undiluted PCRproduct into each well of an opaque fluorimeter plate (Coming Costar,Acton Mass.), allowing the DNA to bind to the reagent. The plate wasscanned in a Fluoroskan II (Labsystems Oy, Helsinki, Finland) to measurethe fluorescence of the sample and to quantify the concentration of DNA.A 5 μl to 10 μl aliquot of the reaction mixture was analyzed byelectrophoresis on a 1% agarose gel to determine which reactions weresuccessful in extending the sequence.

The extended nucleotides were desalted and concentrated, transferred to384-well plates, digested with CviJI cholera virus endonuclease(Molecular Biology Research, Madison Wis.), and sonicated or shearedprior to religation into pUC 18 vector (Amersham Pharmacia Biotech). Forshotgun sequencing, the digested nucleotides were separated on lowconcentration (0.6 to 0.8%) agarose gels, fragments were excised, andagar digested with Agar ACE (Promega). Extended clones were religatedusing T4 ligase (New England Biolabs, Beverly Mass.) into pUC 18 vector(Amersham Pharmacia Biotech), treated with Pfu DNA polymerase(Stratagene) to fill-in restriction site overhangs, and transfected intocompetent E. coli cells. Transformed cells were selected onantibiotic-containing media, and individual colonies were picked andcultured overnight at 37° C. in 384 well plates in LB/2×carb liquidmedia.

The cells were lysed, and DNA was amplified by PCR using Taq DNApolymerase (Amersham Pharmacia Biotech) and Pfu DNA polymerase(Stratagene) with the following parameters: Step 1: 94° C., 3 min; Step2: 94° C., 15 sec; Step 3: 60° C., 1 min; Step 4: 72° C., 2min; Step 5:steps 2, 3, and 4 repeated 29 times; Step 6: 72° C., 5 min; Step 7:storage at 4° C. DNA was quantified by PICOGREEN reagent (MolecularProbes) as described above. Samples with low DNA recoveries werereamplified using the same conditions as described above. Samples werediluted with 20% dimethysulfoxide (1:2, v/v), and sequenced usingDYENAMIC energy transfer sequencing primers and the DYENAMIC DIRECT kit(Amersham Pharmacia Biotech) or the ABI PRISM BIGDYE Terminator cyclesequencing ready reaction kit (Applied Biosystems).

In like manner, full length polynucleotide sequences are verified usingthe above procedure or are used to obtain 5′ regulatory sequences usingthe above procedure along with oligonucleotides designed for suchextension, and an appropriate genomic library.

IX. Labeling and Use of Individual Hybridization Probes

Hybridization probes derived from SEQ ID NO:4-6 are employed to screencDNAs, genomic DNAs, or mRNAs. Although the labeling ofoligonucleotides, consisting of about 20 base pairs, is specificallydescribed, essentially the same procedure is used with larger nucleotidefragments. Oligonucleotides are designed using state-of-the-art softwaresuch as OLIGO 4.06 software (National Biosciences) and labeled bycombining 50 pmol of each oligomer, 250 μCi of [γ-³²P] adenosinetriphosphate (Amersham Pharmacia Biotech), and T4 polynucleotide kinase(DuPont NEN, Boston Mass.). The labeled oligonucleotides aresubstantially purified using a SEPHADEX G-25 superfine size exclusiondextran bead column (Amersham Pharmacia Biotech). An aliquot containing10⁷ counts per minute of the labeled probe is used in a typicalmembrane-based hybridization analysis of human genomic DNA digested withone of the following endonucleases: Ase I, Bgl II, Eco RI, Pst I, Xba I,or Pvu II (DuPont NEN).

The DNA from each digest is fractionated on a 0.7% agarose gel andtransferred to nylon membranes (Nytran Plus, Schleicher & Schuell,Durham N.H.). Hybridization is carried out for 16 hours at 40° C. Toremove nonspecific signals, blots are sequentially washed at roomtemperature under conditions of up to, for example, 0.1×saline sodiumcitrate and 0.5% sodium dodecyl sulfate. Hybridization patterns arevisualized using autoradiography or an alternative imaging means andcompared.

X. Microarrays

The linkage or synthesis of array elements upon a microarray can beachieved utilizing photolithography, piezoelectric printing (ink-jetprinting, See, e.g., Baldeschweiler, supra.), mechanical microspottingtechnologies, and derivatives thereof. The substrate in each of theaforementioned technologies should be uniform and solid with anon-porous surface (Schena (1999), supra). Suggested substrates includesilicon, silica, glass slides, glass chips, and silicon wafers.Alternatively, a procedure analogous to a dot or slot blot may also beused to arrange and link elements to the surface of a substrate usingthermal, UV, chemical, or mechanical bonding procedures. A typical arraymay be produced using available methods and machines well known to thoseof ordinary skill in the art and may contain any appropriate number ofelements. (See, e.g., Schena, M. et al. (1995) Science 270:467-470;Shalon, D. et al. (1996) Genome Res. 6:639-645; Marshall, A. and J.Hodgson (1998) Nat. Biotechnol. 16:27-31.)

Full length cDNAs, Expressed Sequence Tags (ESTs), or fragments oroligomers thereof may comprise the elements of the microarray. Fragmentsor oligomers suitable for hybridization can be selected using softwarewell known in the art such as LASERGENE software (DNASTAR). The arrayelements are hybridized with polynucleotides in a biological sample. Thepolynucleotides in the biological sample are conjugated to a fluorescentlabel or other molecular tag for ease of detection. After hybridization,nonhybridized nucleotides from the biological sample are removed, and afluorescence scanner is used to detect hybridization at each arrayelement. Alternatively, laser desorbtion and mass spectrometry may beused for detection of hybridization. The degree of complementarity andthe relative abundance of each polynucleotide which hybridizes to anelement on the microarray may be assessed. In one embodiment, microarraypreparation and usage is described in detail below.

Tissue or Cell Sample Preparation

Total RNA is isolated from tissue samples using the guanidiniumthiocyanate method and poly(A)⁺ RNA is purified using the oligo-(dT)cellulose method. Each poly(A)⁺ RNA sample is reverse transcribed usingMMLV reverse-transcriptase, 0.05 pg/μl oligo-(dT) primer (21mer), 1×first strand buffer, 0.03 units/μl RNase inhibitor, 500 μM dATP, 500 μMdGTP, 500 μM dTTP, 40 μM dCTP, 40 μM dCTP-Cy3 (BDS) or dCTP-Cy5(Amersham Pharmacia Biotech). The reverse transcription reaction isperformed in a 25 ml volume containing 200 ng poly(A)⁺ RNA withGEMBRIGHT kits (Incyte). Specific control poly(A)⁺ RNAs are synthesizedby in vitro transcription from non-coding yeast genomic DNA. Afterincubation at 37° C. for 2 hr, each reaction sample (one with Cy3 andanother with Cy5 labeling) is treated with 2.5 ml of 0.5M sodiumhydroxide and incubated for 20 minutes at 85° C. to the stop thereaction and degrade the RNA. Samples are purified using two successiveCHROMA SPIN 30 gel filtration spin columns (CLONTECH Laboratories, Inc.(CLONTECH), Palo Alto Calif.) and after combining, both reaction samplesare ethanol precipitated using 1 ml of glycogen (1 mg/ml), 60 ml sodiumacetate, and 300 ml of 100% ethanol. The sample is then dried tocompletion using a SpeedVAC (Savant Instruments Inc., Holbrook N.Y.) andresuspended in 14 μl 5×SSC/0.2% SDS

Microarray Preparation

Sequences of the present invention are used to generate array elements.Each array element is amplified from bacterial cells containing vectorswith cloned cDNA inserts. PCR amplification uses primers complementaryto the vector sequences flanking the cDNA insert. Array elements areamplified in thirty cycles of PCR from an initial quantity of 1-2 ng toa final quantity greater than 5 μg. Amplified array elements are thenpurified using SEPHACRYL-400 (Amersham Pharmacia Biotech).

Purified array elements are immobilized on polymer-coated glass slides.Glass microscope slides (Corning) are cleaned by ultrasound in 0.1% SDSand acetone, with extensive distilled water washes between and aftertreatments. Glass slides are etched in 4% hydrofluoric acid (VWRScientific Products Corporation (VWR), West Chester Pa.), washedextensively in distilled water, and coated with 0.05% aminopropyl silane(Sigma) in 95% ethanol. Coated slides are cured in a 110° C. oven.

Array elements are applied to the coated glass substrate using aprocedure described in U.S. Pat. No. 5,807,522, incorporated herein byreference. 1 μl of the array element DNA, at an average concentration of100 ng/μl, is loaded into the open capillary printing element by ahigh-speed robotic apparatus. The apparatus then deposits about 5 nl ofarray element sample per slide.

Microarrays are UV-crosslinked using a STRATALINKER UV-crosslinker(Stratagene). Microarrays are washed at room temperature once in 0.2%SDS and three times in distilled water. Non-specific binding sites areblocked by incubation of microarrays in 0.2% casein in phosphatebuffered saline (PBS) (Tropix, Inc., Bedford Mass.) for 30 minutes at60° C. followed by washes in 0.2% SDS and distilled water as before.

Hybridization

Hybridization reactions contain 9 μl of sample mixture consisting of 0.2μg each of Cy3 and Cy5 labeled cDNA synthesis products in 5×SSC, 0.2%SDS hybridization buffer. The sample mixture is heated to 65° C. for 5minutes and is aliquoted onto the microarray surface and covered with an1.8 cm² coverslip. The arrays are transferred to a waterproof chamberhaving a cavity just slightly larger than a microscope slide. Thechamber is kept at 100% humidity internally by the addition of 140 μl of5×SSC in a corner of the chamber. The chamber containing the arrays isincubated for about 6.5 hours at 60° C. The arrays are washed for 10 minat 45° C. in a first wash buffer (1×SSC, 0.1% SDS), three times for 10minutes each at 45° C. in a second wash buffer (0.1×SSC), and dried.

Detection

Reporter-labeled hybridization complexes are detected with a microscopeequipped with an Innova 70 mixed gas 10 W laser (Coherent, Inc., SantaClara Calif.) capable of generating spectral lines at 488 nm forexcitation of Cy3 and at 632 nm for excitation of Cy5. The excitationlaser light is focused on the array using a 20× microscope objective(Nikon, Inc., Melville N.Y.). The slide containing the array is placedon a computer-controlled X-Y stage on the microscope and raster-scannedpast the objective. The 1.8 cm×1.8 cm array used in the present exampleis scanned with a resolution of 20 micrometers.

In two separate scans, a mixed gas multiline laser excites the twofluorophores sequentially. Emitted light is split, based on wavelength,into two photomultiplier tube detectors (PMT R1477, Hamamatsu PhotonicsSystems, Bridgewater N.J.) corresponding to the two fluorophores.Appropriate filters positioned between the array and the photomultipliertubes are used to filter the signals. The emission maxima of thefluorophores used are 565 nm for Cy3 and 650 nm for Cy5. Each array istypically scanned twice, one scan per fluorophore using the appropriatefilters at the laser source, although the apparatus is capable ofrecording the spectra from both fluorophores simultaneously.

The sensitivity of the scans is typically calibrated using the signalintensity generated by a cDNA control species added to the samplemixture at a known concentration. A specific location on the arraycontains a complementary DNA sequence, allowing the intensity of thesignal at that location to be correlated with a weight ratio ofhybridizing species of 1:100,000. When two samples from differentsources (e.g., representing test and control cells), each labeled with adifferent fluorophore, are hybridized to a single array for the purposeof identifying genes that are differentially expressed, the calibrationis done by labeling samples of the calibrating cDNA with the twofluorophores and adding identical amounts of each to the hybridizationmixture.

The output of the photomultiplier tube is digitized using a 12-bitRTI-835H analog-to-digital (A/D) conversion board (Analog Devices, Inc.,Norwood Mass.) installed in an IBM-compatible PC computer. The digitizeddata are displayed as an image where the signal intensity is mappedusing a linear 20-color transformation to a pseudocolor scale rangingfrom blue (low signal) to red (high signal). The data is also analyzedquantitatively. Where two different fluorophores are excited andmeasured simultaneously, the data are first corrected for opticalcrosstalk (due to overlapping emission spectra) between the fluorophoresusing each fluorophore's emission spectrum.

A grid is superimposed over the fluorescence signal image such that thesignal from each spot is centered in each element of the grid. Thefluorescence signal within each element is then integrated to obtain anumerical value corresponding to the average intensity of the signal.The software used for signal analysis is the GEMTOOLS gene expressionanalysis program (Incyte).

XI. Complementary Polynucleotides

Sequences complementary to the HPDE-encoding sequences, or any partsthereof, are used to detect, decrease, or inhibit expression ofnaturally occurring HPDE. Although use of oligonucleotides comprisingfrom about 15 to 30 base pairs is described, essentially the sameprocedure is used with smaller or with larger sequence fragments.Appropriate oligonucleotides are designed using OLIGO 4.06 software(National Biosciences) and the coding sequence of HPDE. To inhibittranscription, a complementary oligonucleotide is designed from the mostunique 5′ sequence and used to prevent promoter binding to the codingsequence. To inhibit translation, a complementary oligonucleotide isdesigned to prevent ribosomal binding to the HPDE-encoding transcript.

XII. Expression of HPDE

Expression and purification of HPDE is achieved using bacterial orvirus-based expression systems. For expression of HPDE in bacteria, cDNAis subcloned into an appropriate vector containing an antibioticresistance gene and an inducible promoter that directs high levels ofcDNA transcription. Examples of such promoters include, but are notlimited to, the trp-lac (tac) hybrid promoter and the T5 or T7bacteriophage promoter in conjunction with the lac operator regulatoryelement. Recombinant vectors are transformed into suitable bacterialhosts, e.g., BL21(DE3). Antibiotic resistant bacteria express HPDE uponinduction with isopropyl beta-D-thiogalactopyranoside (IPTG). Expressionof HPDE in eukaryotic cells is achieved by infecting insect or mammaliancell lines with recombinant Autographica californica nuclearpolyhedrosis virus (AcMNPV), commonly known as baculovirus. Thenonessential polyhedrin gene of baculovirus is replaced with cDNAencoding HPDE by either homologous recombination or bacterial-mediatedtransposition involving transfer plasmid intermediates. Viralinfectivity is maintained and the strong polyhedrin promoter drives highlevels of cDNA transcription. Recombinant baculovirus is used to infectSpodoptera frugiperda (Sf9) insect cells in most cases, or humanhepatocytes, in some cases. Infection of the latter requires additionalgenetic modifications to baculovirus. (See Engelhard, E. K. et al.(1994) Proc. Natl. Acad. Sci. USA 91:3224-3227; Sandig, V. et al. (1996)Hum. Gene Ther. 7:1937-1945.)

In most expression systems, HPDE is synthesized as a fusion proteinwith, e.g., glutathione S-transferase (GST) or a peptide epitope tag,such as FLAG or 6-His, permitting rapid, single-step, affinity-basedpurification of recombinant fusion protein from crude cell lysates. GST,a 26-kilodalton enzyme from Schistosoma japonicum, enables thepurification of fusion proteins on immobilized glutathione underconditions that maintain protein activity and antigenicity (AmershamPharmacia Biotech). Following purification, the GST moiety can beproteolytically cleaved from HPDE at specifically engineered sites.FLAG, an 8-amino acid peptide, enables immunoaffinity purification usingcommercially available monoclonal and polyclonal anti-FLAG antibodies(Eastman Kodak). 6-His, a stretch of six consecutive histidine residues,enables purification on metal-chelate resins (QIAGEN). Methods forprotein expression and purification are discussed in Ausubel (1995,supra, ch. 10 and 16). Purified HPDE obtained by these methods can beused directly in the assays shown in Examples XVI, XVII, and XVIII,where applicable.

XIII. Functional Assays

HPDE function is assessed by expressing the sequences encoding HPDE atphysiologically elevated levels in mammalian cell culture systems. cDNAis subcloned into a mammalian expression vector containing a strongpromoter that drives high levels of cDNA expression. Vectors of choiceinclude PCMV SPORT (Life Technologies) and PCR3.1 (Invitrogen, CarlsbadCalif.), both of which contain the cytomegalovirus promoter. 5-10 μg ofrecombinant vector are transiently transfected into a human cell line,for example, an endothelial or hematopoictic cell line, using eitherliposome formulations or electroporation. 1-2 μg of an additionalplasmid containing sequences encoding a marker protein areco-transfected. Expression of a marker protein provides a means todistinguish transfected cells from nontransfected cells and is areliable predictor of cDNA expression from the recombinant vector.Marker proteins of choice include, e.g., Green Fluorescent Protein (GFP;Clontech), CD64, or a CD64-GFP fusion protein. Flow cytometry (FCM), anautomated, laser optics-based technique, is used to identify transfectedcells expressing GFP or CD64-GFP and to evaluate the apoptotic state ofthe cells and other cellular properties. FCM detects and quantifies theuptake of fluorescent molecules that diagnose events preceding orcoincident with cell death. These events include changes in nuclear DNAcontent as measured by staining of DNA with propidium iodide; changes incell size and granularity as measured by forward light scatter and 90degree side light scatter; down-regulation of DNA synthesis as measuredby decrease in bromodeoxyuridine uptake; alterations in expression ofcell surface and intracellular proteins as measured by reactivity withspecific antibodies; and alterations in plasma membrane composition asmeasured by the binding of fluorescein-conjugated Annexin V protein tothe cell surface. Methods in flow cytometry are discussed in Ormerod, M.G. (1994) Flow Cytometry, Oxford, New York N.Y.

The influence of HPDE on gene expression can be assessed using highlypurified populations of cells transfected with sequences encoding HPDEand either CD64 or CD64-GFP. CD64 and CD64-GFP are expressed on thesurface of transfected cells and bind to conserved regions of humanimmunoglobulin G (IgG). Transfected cells are efficiently separated fromnontransfected cells using magnetic beads coated with either human IgGor antibody against CD64 (DYNAL, Lake Success N.Y.). mRNA can bepurified from the cells using methods well known by those of skill inthe art. Expression of mRNA encoding HPDE and other genes of interestcan be analyzed by northern analysis or microarray techniques.

XIV. Production of HPDE Specific Antibodies

HPDE substantially purified using polyacrylamide gel electrophoresis(PAGE; see, e.g., Harrington, M. G. (1990) Methods Enzymol.182:488-495), or other purification techniques, is used to immunizerabbits and to produce antibodies using standard protocols.

Alternatively, the HPDE amino acid sequence is analyzed using LASERGENEsoftware (DNASTAR) to determine regions of high immunogenicity, and acorresponding oligopeptide is synthesized and used to raise antibodiesby means known to those of skill in the art. Methods for selection ofappropriate epitopes, such as those near the C-terminus or inhydrophilic regions are well described in the art. (See, e.g., Ausubel,1995, supra, ch. 11.)

Typically, oligopeptides of about 15 residues in length are synthesizedusing an ABI 431A peptide synthesizer (Applied Biosystems) using FMOCchemistry and coupled to KLH (Sigma-Aldrich, St. Louis Mo.) by reactionwith N-maleimidobenzoyl-N-hydroxysuccinimide ester (MBS) to increaseimmunogenicity. (See, e.g., Ausubel, 1995, supra.) Rabbits are immunizedwith the oligopeptide-KLH complex in complete Freund's adjuvant.Resulting antisera are tested for antipeptide and anti-HPDE activity by,for example, binding the peptide or HPDE to a substrate, blocking with1% BSA, reacting with rabbit antisera, washing, and reacting withradio-iodinated goat anti-rabbit IgG.

XV. Purification of Naturally Occurring HPDE Using Specific Antibodies

Naturally occurring or recombinant HPDE is substantially purified byimmunoaffinity chromatography using antibodies specific for HPDE. Animmunoaffinity column is constructed by covalently coupling anti-HPDEantibody to an activated chromatographic resin, such as CNBr-activatedSEPHAROSE (Amersham Pharmacia Biotech). After the coupling, the resin isblocked and washed according to the manufacturer's instructions.

Media containing HPDE are passed over the immunoaffinity column, and thecolumn is washed under conditions that allow the preferential absorbanceof HPDE (e.g., high ionic strength buffers in the presence ofdetergent). The column is eluted under conditions that disruptantibody/HPDE binding (e.g., a buffer of pH 2 to pH 3, or a highconcentration of a chaotrope, such as urea or thiocyanate ion), and HPDEis collected.

XVI. Identification of Molecules Which Interact with HPDE

HPDE, or biologically active fragments thereof, are labeled with ¹²⁵IBolton-Hunter reagent. (See, e.g., Bolton A. E. and W. M. Hunter (1973)Biochem. J. 133:529-539.) Candidate molecules previously arrayed in thewells of a multi-well plate are incubated with the labeled HPDE, washed,and any wells with labeled HPDE complex are assayed. Data obtained usingdifferent concentrations of HPDE are used to calculate values for thenumber, affinity, and association of HPDE with the candidate molecules.

Alternatively, molecules interacting with HPDE are analyzed using theyeast two-hybrid system as described in Fields, S. and O. Song (1989)Nature 340:245-246, or using commercially available kits based on thetwo-hybrid system, such as the MATCHMAKER system (Clontech).

HPDE may also be used in the PATHCALLING process (CuraGen Corp., NewHaven Conn.) which employs the yeast two-hybrid system in ahigh-throughput manner to determine all interactions between theproteins encoded by two large libraries of genes (Nandabalan, K. et al.(2000) U.S. Pat. No. 6,057,101).

XVII. Demonstration of HPDE Activity

In general, PDE activity of HPDE is measured by monitoring theconversion of a cyclic nucleotide (either cAMP or cGMP) to itsnucleotide monophosphate. The use of tritium-containing substrates suchas ³H-cAMP and ³H-cGMP, and 5′ nucleotidase from snake venom, allows thePDE reaction to be followed using a scintillation counter.

cAMP-specific PDE activity of HPDE is assayed by measuring theconversion of ³H-cAMP to ³H-adenosine in the presence of HPDE and 5′nucleotidase. A one-step assay is run using a 100 μl reaction containing50 mM Tris-HCl pH 7.5, 10 mM MgCl₂, 0.1 unit 5′ nucleotidase (fromCrotalus atrox venom), 0.0062-0.1 μM ³H-cAMP, and various concentrationsof cAMP (0.0062-3 mM). The reaction is started by the addition of 25 μlof diluted enzyme supernatant. Reactions are run directly in mini Poly-Qscintillation vials (Beckman Instruments, Fullerton Calif.). Assays areincubated at 37° C. for a time period that would give less than 15% cAMPhydrolysis to avoid non-linearity associated with product inhibition.The reaction is stopped by the addition of 1 ml of Dowex (Dow Chemical,Midland Mich.) AG1×8 (Cl form) resin (1:3 slurry). Three ml ofscintillation fluid are added, and the vials are mixed. The resin in thevials is allowed to settle for one hour before counting. Solubleradioactivity associated with ³H-adenosine is quantitated using a betascintillation counter. The amount of radioactivity recovered isproportional to the cAMP-specific PDE activity of HPDE in the reaction.For inhibitor or agonist studies, reactions are carried out under theconditions described above, with the addition of 1% DMSO, 50 nM cAMP,and various concentrations of the inhibitor or agonist. Controlreactions are carried out with all reagents except for the enzymealiquot.

cGMP-specific PDE activity of HPDE is assayed by measuring theconversion of ³H-cGMP to ³H-guanosine in the presence of HPDE and 5′nucleotidase. A one-step assay is run using a 100 μl reaction containing50 mM Tris-HCl pH 7.5, 10 mM MgCl₂, 0.1 unit 5′ nucleotidase (fromCrotalus atrox venom), and 0.0064-2.0 μM ³H-cGMP. The reaction isstarted by the addition of 25 μl of diluted enzyme supernatant.Reactions are run directly in mini Poly-Q scintillation vials (BeckmanInstruments). Assays are incubated at 37° C. for a time period thatwould yield less than 15% cGMP hydrolysis in order to avoidnon-linearity associated with product inhibition. The reaction isstopped by the addition of 1 ml of Dowex (Dow Chemical, Midland Mich.)AG1×8 (Cl form) resin (1:3 slurry). Three ml of scintillation fluid areadded, and the vials are mixed. The resin in the vials is allowed tosettle for one hour before counting. Soluble radioactivity associatedwith ³H-guanosine is quantitated using a beta scintillation counter. Theamount of radioactivity recovered is proportional to the cGMP-specificPDE activity of HPDE in the reaction. For inhibitor or agonist studies,reactions are carried out under the conditions described above, with theaddition of 1% DMSO, 50 nM cGMP, and various concentrations of theinhibitor or agonist. Control reactions are carried out with allreagents except for the enzyme aliquot.

Glycerophosphoryl diester phosphodiesterase activity of HPDE is measuredby a coupled spectrophotometric assay utilizing sn-glycerol-3-phosphatedehydrogenase and NAD (Larson, T. J. et al. (1983) J. Biol. Chem.248:5428-5432; Cameron, C. E. et al. (1998) Infect. Immun.66:5763-5770). HPDE is assayed at 25° C. in a 0.5 ml assay mixturecontaining 0.45 ml of 1 M hydrazine-glycine (pH 9.0) buffer, 0.5 M NAD,10 mM CaCl₂, 20 units of glycerol-3-phosphate dehydrogenase (Sigma, St.Louis Mo.), and 0.5 mM glycerophosphorylcholine. Phosphodiesteraseactivity is monitored spectrophotometrically at 340 nm using a molarabsorbance coefficient of 6300 M⁻¹ cm⁻¹ for NADH. Glycerophosphoryldiester phosphodiesterase activity is proportional to the reduction ofNAD.

XVII. Identification of Phosphodiesterase Inhibitors and Agonists

In general, inhibitors and agonists of PDE activity of HPDE can beobtained by screening compounds using the PDE activity assays describedin Example XVII. Enzyme assays are carried out in both the presence andabsence of a candidate compound, and an inhibitor compound is identifiedwhen inhibition of PDE activity of HPDE is observed. Alternatively, anagonist compound is identified when increased PDE activity of HPDE isobserved.

A high-throughput screen for inhibitors of cAMP-specific PDE activity ofHPDE uses microtiter plate-based scintillation proximity assay(Bardelle, C. et al. (1999) Anal. Biochem. 275:148-155). Purified enzymeis diluted in assay buffer containing 25 mM Hepes-NaOH, 1 mM MgCl₂, 0.1mM EGTA, and 0.1% BSA, pH 7.45, at 20° C. A 1% (w/v) suspension ofyttrium silicate beads in 18 mM ZnSO₄ is prepared, and dispensed into amicrotiter plate in 25 μl aliquots. A reaction is initiated by mixing 50μl of the diluted enzyme solution with 50 μl of the assay buffercontaining 2 μM cAMP and 1.8 μCi (4×10⁶ dpm) ³H-cAMP/ml. After 15minutes, a reaction is quenched by heating to 95° C. for 2 minutes andthen cooled, and 50 μl of this quenched solution is added to apre-plated aliquot of the yttrium silicate beads. Alternatively, thereaction is not quenched, and 50 μl of the reaction mixture is addeddirectly to the pre-plated beads. The beads are allowed to settle, themicrotiter plate is sealed, and the reaction mixtures are measured usinga scintillation counter.

Candidate inhibitor compounds are added to individual reaction mixturesto screen for inhibition of PDE activity. Candidate inhibitor moleculesmay be selected from known PDE inhibitors, modified PDE inhibitors,peptide libraries, chemical libraries, and combinatorial chemicallibraries. Inhibitors of cGMP-specific PDE activity of HPDE can beidentified by using the above high-throughput screen with guanosinesubstrates instead of adenosine substrates. Agonists of PDE activity ofHPDE can be identified by using the above high-throughput screen andmonitoring for increased PDE activity instead of decreased PDE activity.Candidate agonist molecules may be selected from known PDE agonists,modified PDE agonists, peptide libraries, chemical libraries, andcombinatorial chemical libraries.

Various modifications and variations of the described methods andsystems of the invention will be apparent to those skilled in the artwithout departing from the scope and spirit of the invention. Althoughthe invention has been described in connection with certain embodiments,it should be understood that the invention as claimed should not beunduly limited to such specific embodiments. Indeed, variousmodifications of the described modes for carrying out the inventionwhich are obvious to those skilled in molecular biology or relatedfields are intended to be within the scope of the following claims.

TABLE 1 Incyte Incyte Incyte Polypeptide Polypeptide PolynucleotidePolynucleotide Project ID SEQ ID NO: ID SEQ ID NO: ID 647189 1 647189CD14 647189CB1 286210 2 286210CD1 5 286210CB1 1700830 3 1700830CD1 61700830CB1

TABLE 2 Incyte Polypeptide Polypeptide GenBank Probability GenBank SEQID NO: ID ID NO: Score Homolog 1 647189CD1 g9453796 3.00E−63 dJ131F15.2(phosphodiesterase I/nucleotide pyrophosphatase 1 (homologous to mouseLy-41 antigen) (PC1, NPPS)) [Homo sapiens] 2 286210CD1 g9948389 2.00E−14Probable glycerophosphoryl diester phosphodiesterase [Pseudomonasaeruginosa] 3 1700830CD1 g6459876 7.00E−15 Glycerophosphoryl diesterphosphodiesterase [Deinococcus radiodurans]

TABLE 3 SEQ Incyte Amino Potential Potential Analytical ID PolypeptideAcid Phosphorylation Glycosylation Signature Sequences, Methods and NO:ID Residues Sites Sites Domains and Motifs Databases 1 647189CD1 477S162 T175 S209 N101 N158 Signal peptide: MOTIFS T262 T2 S419 N292 N329M1-Q24 HMMER Y255 N362 N369 Signal peptide: SPScan N382 N389 M1-S22Transmembrane domains: HMMER I6-L23, Y431-F451 Type I phosphodiesterase:HMMER-PFAM F5-E366 Phosphodiesterase: BLAST- PD003227: V30-E276 PRODOMSomatomedin B: BLAST-DOMO DM02434|P22413|1-517: L31-Y374DM02434|A57080|6-517: D26-Y374 DM02434|A55144|1-561: V30-W139DM02434|P39997|1-469: L31-T242 2 286210CD1 486 S128 T159 S301 N182 N217Transmembrane domain: MOTIFS T423 S484 T164 N233 N255 M380-W401 HMMERS424 S33 T164 N329 N462 Protein phosphodiesterase: BLIMPS- S208 S210S222 PD01922A: K108-P118 PRODOM S318 T479 Y138 PD01922B: P122-D157Protein hydrolase, BLAST- phosphodiesterase: PRODOM PD002136: L111-P2483 1700830CD1 318 S85 S283 T31 N235 Signal peptide: MOTIFS T36 S128 S179M1-G13 SPScan Protein phosphodiesterase: BLIMPS- PD01922A: R38-S48PRODOM PD01922B: L52-D87

TABLE 4 Incyte Polynucleotide Polynucleotide Sequence Selected Sequence5′ 3′ SEQ ID NO: ID Length Fragments Fragments Position Position 4647189CB1 2530 1-1085, 3490552F6 (EPIGNOT01) 505 1203 1-269, 2786107F6(BRSTNOT13) 1491 2016 877-1085 6777323H1 (OVARDIR01) 1 542 3490552T6(EPIGNOT01) 1815 2530 6777323J1 (OVARDIR01) 1116 1817 3702869F6(PENCNOT07) 652 1215 5 286210CB1 2447 1-675, 6340289H1 (BRANDIN01) 13751978 788-814 2697392F6 (UTRSNOT12) 1 581 6334237H1 (BRANDIN01) 1413 20046332977H1 (BRANDIN01) 1896 2447 1004764R6 (BRSTNOT03) 521 130570313183D1 798 1402 6 1700830CB1 1177 1077-1177 70695293V1 614 117770692807V1 1 632

TABLE 5 Polynucleotide Incyte Representative SEQ ID NO: Project IDLibrary 4 647189CB1 BRAPNOT04 5 286210CB1 BRANDIN01 6 1700830CB1BLADTUT05

TABLE 6 Library Vector Library Description BLADTUT05 pINCY Library wasconstructed using RNA isolated from bladder tumor tissue removed from a66- year-old Caucasian male during a radical prostatectomy, radicalcystectomy, and urinary diversion. Pathology indicated grade 3transitional cell carcinoma on the anterior wall of the bladder. Patienthistory included lung neoplasm and tobacco abuse in remission. Familyhistory included malignant breast neoplasm, tuberculosis,cerebrovascular disease, atherosclerotic coronary artery disease, andlung cancer. BRANDIN01 pINCY This normalized pineal gland tissue librarywas constructed from 4 × 10e5 independent clones from a pineal glandtissue library from two different donors. Starting RNA was made frompooled pineal gland tissue removed from two Caucasian females: a68-year-old (donor A) who died from congestive heart failure and a79-year-old (donor B) who died from pneumonia. Neuropathology for donorA indicated mild to moderate Alzheimer disease, atherosclerosis, andmultiple infarctions. Neuropathology for donor B indicated severeAlzheimer disease, arteriolosclerosis, cerebral amyloid angiopathy andmultiple infarctions. There were diffuse and neuritic amyloid plaquesand neurofibrillary tangles throughout the brain sections examined inboth donors. Patient history included diabetes mellitus, rheumatoidarthritis, hyperthyroidism, amyloid heart disease, and dementia in donorA; and pseudophakia, gastritis with bleeding, glaucoma, peripheralvascular disease, COPD, delayed onset tonic/clonic seizures, andtransient ischemic attack in donor B. The library was normalized in oneround using conditions adapted from Soares et al. (1994) Proc. Natl.Acad. Sci. USA 91:9228-9232 and Bonaldo et al. (1996) Genome Res. 6:791,except that a significantly longer (48 hours/round) reannealinghybridization was used. BRAPNOT04 pINCY Library was constructed usingRNA isolated from pons tissue removed from the brain of a 35-year-oldCaucasian male who died from cardiac failure. Pathology indicatedmoderate leptomeningeal fibrosis and multiple microinfarctions of thecerebral neocortex. Microscopically, the cerebral hemisphere revealedmoderate fibrosis of the leptomeninges with focal calcifications. Therewas evidence of shrunken and slightly eosinophilic pyramidal neuronsthroughout the cerebral hemispheres. There were also multiple smallmicroscopic areas of cavitation with surrounding gliosis scatteredthroughout the cerebral cortex. Patient history included dilatedcardiomyopathy, congestive heart failure, cardiomegaly, and an enlargedspleen and liver. Patient medications included simethicone, Lasix,Digoxin, Colace, Zantac, captopril, and Vasotec.

TABLE 7 Program Description Reference Parameter Threshold ABI A programthat removes vector sequences and masks Applied Biosystems, Foster City,CA. FACTURA ambiguous bases in nucleic acid sequences. ABI/ A Fast DataFinder useful in comparing and annotating Applied Biosystems, FosterCity, CA; Mismatch <50% PARACEL amino acid or nucleic acid sequences.Paracel Inc., Pasadena, CA. FDF ABI Auto- A program that assemblesnucleic acid sequences. Applied Biosystems, Foster City, CA. AssemblerBLAST A Basic Local Alignment Search Tool useful in Altschul, S. F. etal. (1990) J. Mol. Biol. ESTs: Probability value = 1.0E−8 or sequencesimilarity search for amino acid and nucleic 215:403-410; Altschul, S.F. et al. (1997) less acid sequences. BLAST includes five functions:blastp, Nucleic Acids Res. 25:3389-3402. Full Length sequences:Probability blastn, blastx, tblastn, and tblastx. value = 1.0E−10 orless FASTA A Pearson and Lipman algorithm that searches for Pearson, W.R. and D. J. Lipman (1988) ESTs: fasta E value = 1.06E−6 similaritybetween a query sequence and a group of Proc. Natl. Acad Sci. USA85:2444-2448; Assembled ESTs: fasta Identity = sequences of the sametype. FASTA comprises as least Pearson, W. R. (1990) Methods Enzymol.95% or greater and five functions: fasta, tfasta, fastx, tfastx, andssearch. 183:63-98; and Smith, T. F. and M. S. Match length = 200 basesor greater; Waterman (1981) Adv. Appl. Math. fastx E value = 1.0E−8 orless 2:482-489. Full Length sequences: fastx score = 100 or greaterBLIMPS A BLocks IMProved Searcher that matches a sequence Henikoff, S.and J. G. Henikoff (1991) Probability value = 1.0E−3 or less againstthose in BLOCKS, PRINTS, DOMO, Nucleic Acids Res. 19:6565-6572; PRODOM,and PFAM databases to search for gene Henikoff, J. G. and S. Henikoff(1996) families, sequence homology, and structural Methods Enzymol.266:88-105; and fingerprint regions. Attwood, T. K. et al. (1997) J.Chem. Inf. Comput. Sci. 37:417-424. HMMER An algorithm for searching aquery sequence against Krogh, A. et al. (1994) J. Mol. Biol., PFAM hits:Probability value = hidden Markov model (HMM)-based databases of235:1501-1531; Sonnhammer, E. L. L. et 1.0E−3 or less protein familyconsensus sequences, such as PFAM. al. (1988) Nucleic Acids Res.26:320-322; Signal peptide hits: Score = 0 or Durbin, R. et al. (1998)Our World View, greater in a Nutshell, Cambridge Univ. Press, pp. 1-350.ProfileScan An algorithm that searches for structural and sequenceGribskov, M. et al. (1988) CABIOS Normalized quality score ≧ GCG- motifsin protein sequences that match sequence 4:61-66; Gribskov, M. et al.(1989) specified “HIGH” value for that patterns defined in Prosite.Methods Enzymol. 183:146-159; Bairoch, particular Prosite motif. A. etal. (1997) Nucleic Acids Generally, score = 1.4-2.1. Res. 25:217-221.Phred A base-calling algorithm that examines automated Ewing, B. et al.(1998) Genome Res. sequencer traces with high sensitivity andprobability. 8:175-185; Ewing, B. and P. Green (1998) Genome Res.8:186-194. Phrap A Phils Revised Assembly Program including SWAT Smith,T. F. and M. S. Waterman (1981) Score = 120 or greater; and CrossMatch,programs based on efficient imple- Adv. Appl. Math. 2:482-489; Smith, T.F. Match length = 56 or greater mentation of the Smith-Watermanalgorithm, useful in and M. S. Waterman (1981) J. Mol. Biol. searchingsequence homology and assembling 147:195-197; and Green, P., DNAsequences. University of Washington, Seattle, WA. Consed A graphicaltool for viewing and editing Gordon, D. et al. (1998) Genome Res. Phrapassemblies. 8:195-202. SPScan A weight matrix analysis program thatscans protein Nielson, H. et al. (1997) Protein Engineer- Score = 3.5 orgreater sequences for the presence of secretory signal ing 10:1-6;Claverie, J. M. and S. Audic peptides. (1997) CABIOS 12:431-439. TMAP Aprogram that uses weight matrices to delineate Persson, B. and P. Argos(1994) J. Mol. transmembrane segments on protein sequences and Biol.237:182-192; Persson, B. and P. determine orientation. Argos (1996)Protein Sci. 5:363-371. TMHMMER A program that uses a hidden Markovmodel (HMM) Sonnhammer, E. L. et al. (1998) Proc. to delineatetransmembrane segments on protein Sixth Intl. Conf. on IntelligentSystems for sequences and determine orientation. Mol. Biol., Glasgow etal., eds., The Am. Assoc. for Artificial Intelligence Press, Menlo Park,CA, pp. 175-182. Motifs A program that searches amino acid sequences forBairoch, A. et al. (1997) Nucleic Acids patterns that matched thosedefined in Prosite. Res. 25:217-221; Wisconsin Package Pro- gram Manual,version 9, page M51-59, Genetics Computer Group, Madison, WI.

1. An isolated polypeptide comprising the full-length amino acidsequence depicted in SEQ ID NO:
 1. 2. An isolated polynueleotideencoding a polypeptide of claim
 1. 3. A recombinant polynucleotidecomprising a promoter sequence operably linked to a polynucleotide ofclaim
 2. 4. A cell transformed with a recombinant polynucleotide ofclaim
 3. 5. A method for producing a polypeptide of claim 1, the methodcomprising: a) culturing a cell under conditions suitable for expressionof the polypeptide, wherein said cell is transformed with a recombinantpolynucleotide, and said recombinant polynucleotide comprises a promotersequence operably linked to a polynucleotide encoding the polypeptide ofclaim 1, and b) recovering the polypeptide so expressed.
 6. An isolatedpolynucleotide selected from the group consisting of: a) apolynucleotide comprising the polynucleotide sequence of SEQ ID NO:4, b)a polynucleotide comprising a naturally occurring polynucleotidesequence having at least 98% sequence identity to the polynucleotidesequence of SEQ ID NO:4, wherein said polynucleotide encodes apolypeptide having phosphodiesterase activity, c) a polynucleotidecomplementary to a), or d) a polynucleotide complementary to b), and e)an RNA equivalent of a)-d).
 7. A composition comprising an effectiveamount of a polypeptide of claim 1 and a pharmaceutically acceptableexcipient.
 8. A microarray wherein at least one element of themicroarray is a polynucleotide of claim
 2. 9. A method of generating anexpression profile of a sample which contains polynucleotides, themethod comprising: a) labeling the polynucleotides of the sample, b)contacting the elements of the microarray of claim 8 with the labeledpolynucleotides of the sample under conditions suitable for theformation of a hybridization complex, and c) quantifying the expressionof the polynucleotides in the sample.
 10. A method for screening acompound for effectiveness as an agonist of a polypeptide according toclaim 1, the method comprising: a) contacting a sample comprising apolypeptide according to claim 1 with a compound; and b) detecting, ifpresent, any agonist activity in the sample.
 11. A method for screeninga compound for effectiveness as an antagonist of a polypeptide accordingto claim 1, the method comprising: a) contacting a sample comprising apolypeptide according to claim 1 with a compound; and b) detecting, ifpresent, any antagonist activity in the sample.
 12. An isolatedpolypeptide consisting of the amino acid sequence of SEQ ID NO: 1.